mm. In possessing a relatively large tympanum and barred thighs, and in

lacking a dorsolateral stripe they are typical of _loquax_, but in the amount of webbing on the hands and feet, broad tarsal stripe, and narrow anal stripe they are like _rickardsi_. The third specimen, a juvenile, has a snout-vent length of 25 mm. In coloration it resembles the adults; it has more distinct bars on the limbs. On the basis of geography these specimens should be _loquax_, for the closest known record of _rickardsi_ is more than 200 kilometers to the northwest, whereas _loquax_ is known from several localities around San Lorenzo.

Shannon and Werler (1955:383) described _Hyla axillamembrana_ from the lower southern slopes of Los Tuxtlas. The unique type is a small male (27 mm. snout-vent). I have examined the type and find no great differences between it and small specimens of _loquax_. It is not possible to determine the color of the thighs, nor was this information given in the description. _Hyla axillamembrana_ is here considered to be a synonym of _Hyla loquax_.

=Hyla microcephala martini= Smith

_Oaxaca_: Donají (15); 43 km. N of Matías Romero (19); Río Sarabia (2); Sarabia (11); Tolosita. _Veracruz_: Acayucan (17); Alvarado (41); Aquilera (21); 8 km. SW of Coatzacoalcos (10); Cosoleacaque (26); 10 km. SE of Hueyapan; Naranja (3); Novillero.

This frog is abundant in the Gulf lowlands of the isthmus, where large breeding congregations were found in grassy ponds on the savannas and in openings in the forest. Most frequently males were calling from grasses and reeds in the ponds; many individuals were perched precariously on thin blades as high as one meter above the water. The call is a series of low squeaks.

Individuals found at night were pale yellow above with light brown lines arranged in an irregular pattern on the back, but often forming a cross or an X-shaped mark in the scapular region. There is a brown stripe from the nostril to the eye and thence to the groin. Anteriorly this stripe is bordered above by a thin white or cream-colored line. Numerous small brown flecks are scattered on the back and dorsal surface of the shank. In most specimens there are thin transverse brown bars on the shank. The thighs and undersides of the limbs are golden yellow; the belly and vocal sac are lemon yellow. The iris is yellowish brown. During the day individuals assume a pale reddish tan ground color with darker brown markings. Twenty-five adult males from Alvarado have an average snout-vent length of 24.1 mm.

=Hyla picta= Günther

_Oaxaca_: Donají (8); Sarabia (11); Tolosita (15); Ubero (6). _Veracruz_: 19 km. N of Acayucan (4); Alvarado (5); Aquilera; 8 km. SW of Coatzacoalcos; 10 km. SE of Hueyapan (7); Lerdo de Tejada; Tula (3).

Widespread in the forests, scrub, and savannas on the Gulf lowlands of the isthmus, these frogs were found breeding at numerous localities. Males call from grasses and bushes growing in and about ponds. The call is a high-pitched insect-like trill. At night these frogs are pale yellow above; they change to light grayish tan during the day. A dark stripe extends from the nostril to the eye and thence posteriorly to a point between the axilla and groin. Above this dark stripe is a broader white stripe. Scattered on the dorsum are brown flecks or spots; the shanks are marked with poorly-defined cross-bars. The thighs are deep yellow below and paler above with scattered dark flecks. The belly is white, and the vocal sac is yellow. The iris is golden. Twenty males have an average snout-vent length of 21.5 mm.; three females, 24.0 mm.

=Hyla robertmertensi= Taylor

_Oaxaca_: Tapanatepec (28); 7.5 km. NW of Tapanatepec (38); 7.2 km. WNW of Zanatepec (77).

This species was found in the isthmian region only on the Pacific lowlands at the southern base of the western part of the Sierra Madre de Chiapas. On July 13, 1956, many large choruses were discovered. The calling males were on reeds and thorn scrub in and at the edge of temporary ponds; the call is a cricket-like "creak-creack," quickly followed by a series of notes "creak-eek-eek-eek-eek."

At night the dorsal ground color is pale yellow; this changes to pinkish buff during the day. There is a grayish or brown dark stripe from the nostril to the eye; the stripe continues to the groin. This dark stripe is bordered above by a narrow white stripe. The belly is white, and the vocal sac is yellow. The iris is dull reddish brown. Twenty-five males have an average snout-vent length of 24.7 mm.

=Hyla staufferi= Cope

_Oaxaca_: Chivela; Huilotepec (5); Juchitán (4); Matías Romero (4); 25 km. N of Matías Romero; Mixtequilla (4); Río Sarabia (11); 11 km. S of Santiago Chivela; Sarabia (3); Tapanatepec (67); Tehuantepec (66); Tolosita (2); Ubero; Unión Hidalgo; Zanatepec (6). _Veracruz_: Acayucan (7); Alvarado (3); Amatitlán; Aquilera; Ciudad Alemán (3); 8 km. SW of Coatzacoalcos (9); Cosamaloapan (4); Cosoleacaque (8); 10 km. SE of Hueyapan; Lerdo de Tejada; Novillero (6); Tula (2).

This is the only species of small hylid that crosses the isthmus. Calling males were found in and about ponds on the savannas in southern Veracruz, in ponds in open forest in northern Oaxaca (not in forest pools), and in temporary pools in the scrub forest on the Pacific lowlands. Individuals usually called from bushes and reeds in or at the edge of ponds. The call is a short "braaa." Dates of breeding choruses indicate that by the time the other small species of hylids in the Gulf lowlands reach the peak of their breeding season, that of _H. staufferi_ is essentially over; no large breeding congregations were found in July. On July 8, 1956, two metamorphosing young were found clinging to blades of grass in a pond; they had snout-vent lengths of 8 and 9 mm. and tail stumps less than 3 mm. in length. Others were found on July 13 and 26. The juveniles are nearly unicolor olive green above and white below.

In life the adults vary greatly in color pattern. The dorsal ground color is yellowish tan to olive brown with olive brown or dark brown spots, some of which in certain individuals are connected to form longitudinal dark stripes. On the posterior surface of the thighs are small white flecks. The belly is white, and the vocal sac is a rich yellow. Twenty males have an average snout-vent length of 26.3 mm.; they have no horny nuptial pads. No noticeable differences in either color or body proportions were found between the populations on either side of the isthmus.

=Hylella sumichrasti= Brocchi

_Oaxaca_: Cerro Arenal (5); Cerro San Pedro (2); Escurano; La Concepción (41); Portillo Los Nanches (6); San Antonio (16); 11 km. S of Santiago Chivela (18); Santa Lucía (7); Tapanatepec (5); Tehuantepec (8); Tenango (49); Tres Cruces (19).

With the exception of the series from 11 kilometers south of Santiago Chivela, most of these specimens were found in small arboreal bromeliads during the dry season. Males were found along a clear, shallow, rocky stream south of Santiago Chivela on July 6, 1956. The frogs were calling from bushes and rocks in and along the stream. When disturbed, they jumped into the water and floated downstream until they were able to hold onto a rock or other object. The call is a loud "bra-a-ah." In breeding individuals the dorsum is pale yellow; the belly is white, and the vocal sac is yellow. The iris is pale golden yellow. Eighteen males have an average snout-vent length of 25.2 mm. All have dark brown nuptial tuberosities on the pollex.

Certain diagnostic characters of this species as given by Taylor (1943a:50) and Taylor and Smith (1945:598) are in need of revision. _Hylella sumichrasti_ has been characterized as having no vocal sac, rarely having vomerine teeth, and as having a relatively smooth throat. The vocal sac in breeding males is quite evident; it is single, median, and when expanded, spherical. The openings into the vocal sac are narrow slits along the inner posterior border of the jaw rami. Of 151 specimens studied, 74 have vomerine ridges between the choanae, and 36 of these have one to three teeth on each ridge. The belly and undersurfaces of the thighs are granular; the throat is only somewhat less so. The granular condition may be correlated with breeding, for specimens obtained from bromeliads in the dry season had rather smooth throats. It seems that the vocal sac atrophys in the non-breeding season. These seasonal changes may account for the diagnoses given by Taylor (_op. cit._) and Taylor and Smith (_op. cit._); likewise, since many of the specimens obtained by Smith in the dry season were juveniles and subadults, the development of the vomerine ridges could not be diagnosed properly.

The range of this species encompasses the Pacific slopes of the Isthmus of Tehuantepec eastward to the upper Cintalapa Valley and vicinity of Tonalá in western Chiapas. Priscilla Starrett collected tadpoles of _H. sumichrasti_ from a stream 19 km. N of Arriaga, Chiapas. These limited observations on the ecology of this frog suggest that it breeds in the fast-moving streams of the Pacific slopes, and that it seeks shelter in arboreal bromeliads during the dry season.

=Phrynohyas modesta= Taylor and Smith

_Oaxaca_: Tuxtepec. _Veracruz_: 20 km. S of Jesús Carranza; 20 km. ENE of Jesús Carranza (2); Minatitlán.

I have not collected this species in the isthmus. The locality records indicate that the range is discontinuous (Duellman, 1956:27). The species occurs on the humid Pacific slopes from south-central Chiapas eastward to El Salvador and on the humid Gulf lowlands from southern Veracruz eastward into Tabasco, but is unknown from the dry Pacific slopes and plains in the isthmus.

The acquisition of several specimens of this species in southern Veracruz, Tabasco, and Oaxaca, together with a knowledge of the variation displayed by _Phrynohyas spilomma_, suggests that _modesta_ may be a color variety of _spilomma_.

=Phrynohyas spilomma= Cope

_Oaxaca_: Tapanatepec (3). _Veracruz_: Amatitlán (12); Chacaltianguis (2); Ciudad Alemán (6); Cosamaloapan; Novillero (3).

Like the preceding species, this frog is unknown from the arid Pacific lowlands of the isthmus; its presence at Tapanatepec, a locality situated in more mesic conditions than prevail on the Plains of Tehuantepec, indicates that it may have a distribution on the Pacific slopes much like that of _P. modesta_. Furthermore, this frog was not detected in the rainforests of the Gulf lowlands; in that region it was found only in scrub forest and savanna.

On July 26, 1956, numerous choruses of these frogs were heard between Ciudad Alemán and Tlacotalpan, Veracruz. The call is a loud, nasal "grawl" repeated continuously. The males call from the water. Several clasping pairs were found in shallow grassy ponds amidst the scrub forest. The ground color varies from reddish brown to tan with dark brown dorsal markings. The iris is golden, and the vocal sacs are dark olive brown. After a light shower during the dry season, six individuals were found on the low branches of trees at night near Ciudad Alemán.

=Phyllomedusa callidryas taylori= Funkhouser

_Oaxaca_: Donají (9); Sarabia (8); Tolosita (6); Ubero (27). _Veracruz_: Alvarado (7); Aquilera; Berta; Coatzacoalcos (9); 10 km. SE of Hueyapan (5); Naranja (17).

In life this frog presents a striking array of colors. The dorsum varies from pale green to dark olive green; there may be scattered whitish or cream-colored spots on the back. On the flanks are bright yellow to deep cream-colored vertical bars separated by pale blue or purple interspaces. The thighs and undersurfaces of the hind limbs are golden orange; the belly is yellow, and the throat is cream-colored. The iris is crimson; the transparent part of the lower eyelid has golden reticulations. When the frog is resting, the forefeet are folded beneath the throat, and the limbs are folded tightly against the body. In this position and with the eyes closed and head flattened, this gaudy frog assumes the appearance of a small elliptical green leaf.

Throughout the month of July, 1956, _Phyllomedusa_ was breeding in ponds in or adjacent to the rainforest in northern Oaxaca and in southern Veracruz. Only at Alvarado was it found breeding in a grassy pond. Males and females alike were found on bushes and trees in and around the ponds. The call is a single "wank." Amplexing males continue to call, but the call is softer and less nasal in quality. The eggs are encased in pale green gelatin and attached to leaves on branches overhanging the water. Three egg clutches contained 38, 41, and 46 eggs.

=Phyllomedusa dacnicolor= Cope

_Oaxaca_: Escurano; Tehuantepec.

Although it is abundant on the Pacific lowlands to the northwest in Guerrero, Michoacán, and Colima, this species is known only from two specimens from Tehuantepec. There is no apparent physical barrier to their distribution in the isthmus; in the Balsas Basin the species lives in a hotter, more arid environment than that at Tehuantepec.

=Gastrophryne usta= Cope

_Oaxaca_: Santa Efigenia; Tehuantepec (10); 24 km. W of Tehuantepec; Tolosita (2). _Veracruz_: Ayentes (6); La Oaxaqueña; Novillero (2); San Lorenzo.

Calling males were found in open scrub forest near Tehuantepec and in savannas near Novillero. The specimens from Tolosita were found under cover in a clearing in the forest (Fugler and Webb, 1957:106).

Specimens from the Pacific lowlands are typical of _Gastrophryne usta gadowi_ Boulenger in possessing a thin line on the posterior surface of the thighs and a thin line from the snout to the vent. Of nine specimens from the Gulf lowlands (Ayentes, Novillero, and San Lorenzo), seven have a middorsal line; this is narrow in four and wide in three. Five have the stripes on the thighs. Two specimens from the middle of the isthmus (Tolosita) have no stripes on the thighs; one has a thin middorsal line, and the other has a broad line. The adult males have a black throat; females have a mottled one. The brown reticulations on the bellies of specimens from the Gulf lowlands is bolder than on specimens from the Pacific lowlands. The presence of certain characters supposedly diagnostic of the subspecies _gadowi_ (line on dorsum and thighs) in the population of _usta_ in southern Veracruz suggests that a redefinition of the ranges of these subspecies will be in order when sufficient material is available to delimit them accurately. For the present I prefer to consider all specimens from the isthmus solely as _Gastrophryne usta_ without referring them to subspecies.

=Rana palmipes= Spix

_Oaxaca_: Matías Romero (11); 11 km. S of Santiago Chivela; Santo Domingo; Sarabia. _Veracruz_: Coatzacoalcos; Cuatotolapam; 25 km. SE of Jesús Carranza (4); Tlacotalpan (2); Tula.

Adults were found along streams and in marshes in savannas and rainforest. These frogs are wary and difficult to capture, even at night. _Rana palmipes_ is another species that has a discontinuous distribution in the isthmus. The species does not occur on the Pacific lowlands of the isthmus, but does occur on the more humid Pacific slopes of Chiapas and Guatemala.

Tadpoles were found in a small sluggish tributary to the Río Sarabia.

=Rana pipiens= Schreber

_Oaxaca_: Agua Caliente; Cerro Quiengola; Escurano (14); Río Sarabia (2); Tapanatepec (5); Tehuantepec (24). _Veracruz_: Acayucan; Cuatotolapam (15); Jesús Carranza (2); 20 km. S of Jesús Carranza (11); 25 km. SE of Jesús Carranza; 20 km. ENE of Jesús Carranza (10); San Lorenzo (10).

As in most other places in México and northern Central America, this species occurs wherever there is permanent water. Males were heard calling from woodland ponds and from savanna ponds.

SUMMARY

Investigations of the amphibians and their environments in the Isthmus of Tehuantepec have been presented with the aim of gaining an understanding of the present biological and of the historical events responsible for the present patterns of distribution of amphibians in this region.

The Isthmus of Tehuantepec embraces three major environments--savanna, semi-arid scrub forest, and quasi-rainforest. The rainforest presents an environment noticeably different from the other two and has a different amphibian fauna.

Analysis of present patterns of distribution shows that certain species are restricted to the rainforests on the Gulf lowlands; others live only in the semi-arid scrub forests on the Pacific lowlands. A third group of species lives on both the Gulf and Pacific lowlands; most of these species occur only in the scrub forests or savannas on the Gulf lowlands, but some also inhabit the rainforest. In one way or another the isthmus presents a barrier to the distribution of 75 per cent of the species of amphibians living in the lowlands; it is a greater barrier still to the species inhabiting the highlands on either side.

Present patterns of distribution are attributed to bioclimatic fluctuation in the Pleistocene. In the course of these climatic shifts, tropical environments and their amphibian inhabitants seem to have survived in the isthmian region.

The amphibian fauna of the lowlands of the Isthmus of Tehuantepec consists of 16 genera and 36 species. Systematic studies of all available specimens from the region show that _Eleutherodactylus conspicuus_ Taylor and Smith is a synonym of _Eleutherodactylus alfredi_ Boulenger and that _Hyla axillamembrana_ Shannon and Werler is a synonym of _Hyla loquax_ Gaige and Stuart.

LITERATURE CITED

BEARD, J. S.

1953. The savanna vegetation of northern tropical America. Ecol. Mono., vol. 23 (2):149-215.

BOULENGER, G. A.

1898. Fourth report on additions to the batrachian collection in the Natural History Museum. Proc. Zool. Soc. London, 1898, pp. 473-482, pls. 38-39.

BURT, C. E.

1931. A study of the teiid lizards of the genus _Cnemidophorus_ with special reference to their phylogenetic relationships. Bull. U. S. Nat. Mus., No. 154, pp. viii + 286.

CONTRERAS A., A.

1942. Mapa de las provincias climatologias de la Republica Mexicana. México, D. F., Dirección de Geografía, Meterología e Hidrología, pp. i-xxviii, tables 1-54, 2 maps.

COOKE, C. W.

1945. Geology of Florida. Florida Geol. Surv., Geol. Bull., No. 29:1-339.

DORF, E.

1959. Climatic changes of the past and present. Contrib. Mus. Paleo. Univ. Michigan, vol. 13 (8):181-210.

DUELLMAN, W. E.

1956. The frogs of the hylid genus _Phrynohyas_ Fitzinger, 1843. Miscl. Publ. Mus. Zool. Univ. Michigan, No. 96:1-47, pls. 1-6.

1958a. A monographic study of the colubrid snake genus _Leptodeira_. Bull. Amer. Mus. Nat. Hist., vol. 114:1-152, pls. 1-31.

1958b. A preliminary analysis of the herpetofauna of Colima, Mexico. Occas. Papers Mus. Zool. Univ. Michigan, No. 589:1-22.

1958c. A review of the frogs of the genus _Syrrhophus_ in western Mexico. Occas. Papers Mus. Zool. Univ. Michigan, No. 594:1-15, pls. 1-3.

DUELLMAN, W. E., and SCHWARTZ, A.

1958. Amphibians and reptiles of southern Florida. Bull. Florida State Mus., vol. 3 (5):181-324.

DUNN, E. R.

1942. The American caecilians. Bull. Mus. Comp. Zool., vol. 91 (6):439-540.

DURHAM, J. W., ARELLANO, A. R. V., and PECK, JR., J. H.

1952. No Cenozoic Tehuantepec seaways. Bull. Geol. Soc. Amer., vol. 63:1245.

FIRSCHEIN, I. L.

1950. A new toad from Mexico with a redefinition of the _cristatus_ group. Copeia, 1950 (2):81-87, pl. 1.

1954. Definition of some little-understood members of the leptodactylid genus _Syrrhophus_, with a description of a new species. Copeia, 1954 (1):48-58.

FIRSCHEIN, I. L., and SMITH, H. M.

1957. A high-crested race of toad (_Bufo valliceps_) and other noteworthy reptiles and amphibians from southern Mexico. Herpetologica, vol. 13 (3):219-222.

FUGLER, C. M., and WEBB, R. G.

1957. Some noteworthy reptiles and amphibians from the states of Oaxaca and Veracruz. Herpetologica, vol. 13 (2):103-108.

GLOYD, H. K.

1940. The rattlesnakes, genera _Sistrurus_ and _Crotalus_. Chicago Acad. Sci. Special Publ., No. 4, vii + 266 pp., pls. 1-31.

GOIN, C. J.

1958. Comments upon the origin of the herpetofauna of Florida. Quart. Jour. Florida Acad. Sci., vol. 21 (1):61-70.

GOLDMAN, E. A.

1951. Biological investigations in Mexico. Smithsonian Misc. Publ., vol. 115, xiii + 476 pp., pls. 1-71.

GOODNIGHT, C. J., and GOODNIGHT, M. L.

1956. Some observations in a tropical rain forest in Chiapas, Mexico. Ecology, vol. 37 (1):139-150.

GRISCOM, L.

1932. The distribution of bird-life in Guatemala. Bull. Amer. Mus. Nat. Hist., vol. 64:1-439.

1950. Distribution and origin of the birds of Mexico. Bull. Mus. Comp. Zool., vol. 103:341-382.

HARTWEG, N., and OLIVER, J. A.

1940. A contribution to the herpetology of the Isthmus of Tehuantepec. IV. An annotated list of the amphibians and reptiles collected on the Pacific slope during the summer of 1936. Misc. Publ. Mus. Zool. Univ. Michigan, No. 47:1-31.

HUBBELL, T. H.

1954. Relationships and distribution of _Mycotrupes_. In The burrowing beetles of the genus _Mycotrupes_, Olson, A. L., Hubbell, T. H., and Howden, H. F. Misc. Publ. Mus. Zool. Univ. Michigan, No. 84:1-59, pls. 1-8.

HUTCHINSON, G. E., PATRICK, R., and DEEVEY, E. S.

1956. Sediments of Lake Patzcuaro, Michoacán, Mexico. Bull. Geol. Soc. Amer., vol. 67:1491-1504.

LANGEBARTEL, D. A., and SMITH, P. W.

1959. Noteworthy records of amphibians and reptiles from eastern Mexico. Herpetologica, vol. 15 (1):27-29.

MARTIN, P. S.

1958. Pleistocene ecology and biogeography of North America. Zoogeography. Amer. Assoc. Advanc. Sci., Publ. No. 51:375-420.

MARTIN, P. S., and HARRELL, B. E.

1957. The Pleistocene history of temperate biotas in Mexico and eastern United States. Ecology, vol. 38:468-480.

OLIVER, J. A.

1948. The relationships and zoogeography of the genus _Thalerophis_ Oliver. Bull. Amer. Mus. Nat. Hist., vol. 92:157-280, pls. 16-19.

OLSON, E. C., and MCGREW, P. O.

1941. Mammalian fauna from the Pliocene of Honduras. Bull. Geol. Soc. Amer., vol. 52:1219-1244.

RUTHVEN, A. G.

1912. The amphibians and reptiles collected by the University of Michigan--Walker Expedition in southern Vera Cruz, Mexico. Zool. Jahrbuch, vol. 32 (4):295-332, pls. 6-11.

SCHUCHERT, C.

1935. Historical geology of the Antillean-Caribbean region. New York, xxvi + 811 pp.

SEARS, P. B., FOREMAN, F., and CLISBY, K. H.

1955. Palynology in southern North America. Bull. Geol. Soc. Amer., vol. 66:471-530.

SHANNON, F. A., and WERLER, J.

1955. Notes on amphibians of the Los Tuxtlas Range of Veracruz, Mexico. Trans. Kansas Acad. Sci., vol. 58 (3):360-386.

SHREVE, B.

1957. Reptiles and amphibians from the Selva Lacandona. _In_ Biological Investigations in the Selva Lacandona, Chiapas, Mexico. Paynter, R. A. (editor). Bull. Mus. Comp. Zool., vol. 116 (4):193-298.

SMITH, H. M.

1947. Notes on Mexican amphibians and reptiles. Jour. Washington Acad. Sci., vol. 37:408-412.

SMITH, H. M., and LAUFE, L. E.

1946. A summary of Mexican Lizards of the genus _Ameiva_. Univ. Kansas Sci. Bull., vol. 31 (2):7-73.

SMITH, H. M., and TAYLOR, E. H.

1950. An annotated checklist and key to the reptiles of Mexico exclusive of the snakes. Bull. U. S. Natl. Mus., No. 199, v + 253 pp.

STIRTON, R. A.

1954. Late Miocene mammals from Oaxaca, Mexico. Amer. Jour. Sci., No. 252:634-638.

STUART, L. C.

1935. A contribution to a knowledge of the herpetology of a portion of the savanna region of central Petén, Guatemala. Misc. Publ. Mus. Zool. Univ. Michigan, No. 29:1-56, pls. 1-4.

1941. Studies of Neotropical Colubridae VIII. A revision of the genus _Dryadophis_ Stuart, 1939. Misc. Publ. Mus. Zool. Univ. Michigan, No. 49:1-106, pls. 1-4.

1951. The herpetofauna of the Guatemalan Plateau, with special reference to its distribution on the southwestern highlands. Contrib. Lab. Vertebrate Biol., Univ. Michigan, No. 49:1-71, pls. 1-7.

1954. A description of a subhumid corridor across northern Central America, with comments on its herpetofaunal indicators. Contrib. Lab. Vertebrate Biol., Univ. Michigan, No. 65:1-26, pls. 1-6.

1958. A study of the herpetofauna of the Uaxactun-Tikal area of northern El Petén, Guatemala. Contrib. Lab. Vertebrate Biol., Univ. Michigan, No. 75:1-30.

TAYLOR, E. H.

1940. New species of Mexican Anura. Univ. Kansas Sci. Bull., vol. 26 (11):385-405.

1941. New amphibians from the Hobart M. Smith Mexican collections. Univ. Kansas Sci. Bull., vol. 27 (8):141-167.

1942. The frog genus _Diaglena_ with a description of a new species. Univ. Kansas Sci. Bull., vol. 28 (4):57-65.

1943a. A new _Hylella_ from Mexico. Proc. Biol. Soc. Washington, vol. 56:49-52.

1943b. Herpetological novelties from Mexico. Univ. Kansas Sci. Bull., vol. 29 (8):343-361.

TAYLOR, E. H., and SMITH, H. M.

1945. Summary of the collections of amphibians made in Mexico under the Walter Rathbone Bacon Traveling Scholarship. Proc. U. S. Natl. Mus., vol. 95:521-613, pls. 18-32.

TRASK, P. D., PHLEGER, F. B., and STETSON, H. C.

1947. Recent changes in sedimentation in the Gulf of Mexico. Science, vol. 106:460-461.

WEYL, R.

1955. Vestigios de una glaciacion del Pleistoceno en la Cordillera de Talamanca, Costa Rica, A. C. Informe Trimestral, Inst. Geog. de Costa Rica, pp. 9-32.

WHITE, S. E.

1956. Probable substages of glaciation on Ixtaccihuatl, Mexico. Jour. Geol., vol. 64:289-295.

WILLIAMS, L.

1939. Arboles y arbustos del Istmos de Tehuantepec, Mexico. Lilloa., vol. 4:137-171.

_Transmitted May 23, 1960._

UNIVERSITY OF KANSAS PUBLICATIONS MUSEUM OF NATURAL HISTORY

Institutional libraries interested in publications exchange may obtain this series by addressing the Exchange Librarian, University of Kansas Library, Lawrence, Kansas. Copies for individuals, persons working in a particular field of study, may be obtained by addressing instead the Museum of Natural History, University of Kansas, Lawrence, Kansas. There is no provision for sale of this series by the University Library, which meets institutional requests, or by the Museum of Natural History, which meets the requests of individuals. However, when individuals request copies from the Museum, 25 cents should be included, for each separate number that is 100 pages or more in length, for the purpose of defraying the costs of wrapping and mailing.

* An asterisk designates those numbers of which the Museum's supply (not the Library's supply) is exhausted. Numbers published to date, in this series, are as follows:

Vol. 1. Nos. 1-26 and index. Pp. 1-638, 1946-1950.

*Vol. 2. (Complete) Mammals of Washington. By Walter W. Dalquest. Pp. 1-444, 140 figures in text. April 9, 1948.

Vol. 3. *1. The avifauna of Micronesia, its origin, evolution, and distribution. By Rollin H. Baker. Pp. 1-359, 16 figures in text. June 12, 1951.

*2. A quantitative study of the nocturnal migration of birds. By George H. Lowery, Jr. Pp. 361-472, 47 figures in text. June 29, 1951.

3. Phylogeny of the waxwings and allied birds. By M. Dale Arvey. Pp. 473-530, 49 figures in text, 13 tables. October 10, 1951.

4. Birds from the state of Veracruz, Mexico. By George H. Lowery, Jr., and Walter W. Dalquest. Pp. 531-649, 7 figures in text, 2 tables. October 10, 1951.

Index. Pp. 651-681.

*Vol. 4. (Complete) American weasels. By E. Raymond Hall. Pp. 1-466, 41 plates, 31 figures in text. December 27, 1951.

Vol. 5. Nos. 1-37 and index. Pp. 1-676, 1951-1953.

*Vol. 6. (Complete) Mammals of Utah, _taxonomy and distribution_. By Stephen D. Durrant. Pp. 1-549, 91 figures in text, 80 tables. August 10, 1952.

Vol. 7. *1. Mammals of Kansas. By E. Lendell Cockrum. Pp. 1-303, 73 figures in text, 37 tables. August 25, 1952.

2. Ecology of the opossum on a natural area in northeastern Kansas. By Henry S. Fitch and Lewis L. Sandidge. Pp. 305-338, 5 figures in text. August 24, 1953.

3. The silky pocket mice (Perognathus flavus) of Mexico. By Rollin H. Baker. Pp. 339-347, 1 figure in text. February 15, 1954.

4. North American jumping mice (Genus Zapus). By Philip H. Krutzsch. Pp. 349-472, 47 figures in text, 4 tables. April 21, 1954.

5. Mammals from Southeastern Alaska. By Rollin H. Baker and James S. Findley. Pp. 473-477. April 21, 1954.

6. Distribution of Some Nebraskan Mammals. By J. Knox Jones, Jr. Pp. 479-487. April 21, 1954.

7. Subspeciation in the montane meadow mouse. Microtus montanus, in Wyoming and Colorado. By Sydney Anderson. Pp. 489-506, 2 figures in text. July 23, 1954.

8. A new subspecies of bat (Myotis velifer) from southeastern California and Arizona. By Terry A. Vaughan. Pp. 507-512. July 23, 1954.

9. Mammals of the San Gabriel mountains of California. By Terry A. Vaughan. Pp. 513-582, 1 figure in text, 12 tables. November 15, 1954.

10. A new bat (Genus Pipistrellus) from northeastern Mexico. By Rollin H. Baker. Pp. 583-586. November 15, 1954.

11. A new subspecies of pocket mouse from Kansas. By E. Raymond Hall. Pp. 587-590. November 15, 1954.

12. Geographic variation in the pocket gopher, Cratogeomys castanops, in Coahuila, Mexico. By Robert J. Russell and Rollin H. Baker. Pp. 591-608. March 15, 1955.

13. A new cottontail (Sylvilagus floridanus) from northeastern Mexico. By Rollin H. Baker. Pp. 609-612. April 8, 1955.

14. Taxonomy and distribution of some American shrews. By James S. Findley. Pp. 613-618. June 10, 1955.

15. The pigmy woodrat, Neotoma goldmani, its distribution and systematic position. By Dennis G. Rainey and Rollin H. Baker. Pp. 619-624. 2 figures in text. June 10, 1955.

Index. Pp. 625-651.

Vol. 8. 1. Life history and ecology of the five-lined skink, Eumeces fasciatus. By Henry S. Fitch. Pp. 1-156, 26 figures in text. September 1, 1954.

2. Myology and serology of the Avian Family Fringillidae, a taxonomic study. By William B. Stallcup. Pp. 157-211, 23 figures in text, 4 tables. November 15, 1954.

3. An ecological study of the collared lizard (Crotaphytus collaris). By Henry S. Fitch. Pp. 213-274, 10 figures in text. February 10, 1956.

4. A field study of the Kansas ant-eating frog, Gastrophryne olivacea. By Henry S. Fitch. Pp. 275-306, 9 figures in text. February 10, 1956.

5. Check-list of the birds of Kansas. By Harrison B. Tordoff. Pp. 307-359, 1 figure in text. March 10, 1956.

6. A population study of the prairie vole (Microtus ochrogaster) in northeastern Kansas. By Edwin P. Martin. Pp. 361-416, 19 figures in text. April 2, 1956.

7. Temperature responses in free-living amphibians and reptiles of northeastern Kansas. By Henry S. Fitch. Pp. 417-476, 10 figures in text, 6 tables. June 1, 1956.

8. Food of the crow, Corvus brachyrhynchos Brehm, in south-central Kansas. By Dwight Platt. Pp. 477-498, 4 tables. June 8, 1956.

9. Ecological observations on the woodrat, Neotoma floridana. By Henry S. Fitch and Dennis G. Rainey. Pp. 499-533, 3 figures in text. June 12, 1956.

10. Eastern woodrat, Neotoma floridana: Life history and ecology. By Dennis G. Rainey. Pp. 535-646, 12 plates, 13 figures in text. August 15, 1956.

Index. Pp. 647-675.

Vol. 9. 1. Speciation of the wandering shrew. By James S. Findley. Pp. 1-68, 18 figures in text. December 10, 1955.

2. Additional records and extensions of ranges of mammals from Utah. By Stephen D. Durrant, M. Raymond Lee, and Richard M. Hansen. Pp. 69-80. December 10, 1955.

3. A new long-eared myotis (Myotis evotis) from northeastern Mexico. By Rollin H. Baker and Howard J. Stains. Pp. 81-84. December 10, 1955.

4. Subspeciation in the meadow mouse, Microtus pennsylvanicus, in Wyoming. By Sydney Anderson. Pp. 85-104, 2 figures in text. May 10, 1956.

5. The condylarth genus Ellipsodon. By Robert W. Wilson. Pp. 105-116, 6 figures in text. May 19, 1956.

6. Additional remains of the multituberculate genus Eucosmodon. By Robert W. Wilson. Pp. 117-123, 10 figures in text. May 19, 1956.

7. Mammals of Coahuila, Mexico. By Rollin H. Baker. Pp. 125-335, 75 figures in text. June 15, 1956.

8. Comments on the taxonomic status of Apodemus peninsulae, with description of a new subspecies from North China. By J. Knox Jones, Jr. Pp. 337-346, 1 figure in text, 1 table. August 15, 1956.

9. Extensions of known ranges of Mexican bats. By Sydney Anderson. Pp. 347-351. August 15, 1956.

10. A new bat (Genus Leptonycteris) from Coahuila. By Howard J. Stains. Pp. 353-356. January 21, 1957.

11. A new species of pocket gopher (Genus Pappogeomys) from Jalisco, Mexico. By Robert J. Russell. Pp. 357-361. January 21, 1957.

12. Geographic variation in the pocket gopher, Thomomys bottae, in Colorado. By Phillip M. Youngman. Pp. 363-384, 7 figures in text. February 21, 1958.

13. New bog lemming (genus Synaptomys) from Nebraska. By J. Knox Jones, Jr. Pp. 385-388. May 12, 1958.

14. Pleistocene bats from San Josecito Cave, Nuevo León, México. By J. Knox Jones, Jr. Pp. 389-396. December 19, 1958.

15. New Subspecies of the rodent Baiomys from Central America. By Robert L. Packard. Pp. 397-404. December 19, 1958.

16. Mammals of the Grand Mesa, Colorado. By Sydney Anderson. Pp. 405-414, 1 figure in text. May 20, 1959.

17. Distribution, variation, and relationships of the montane vole, Microtus montanus. By Emil K. Urban. Pp. 415-511. 12 figures in text, 2 tables. August 1, 1959.

18. Conspecificity of two pocket mice, Perognathus goldmani and P. artus. By E. Raymond Hall and Marilyn Bailey Ogilvie. Pp. 513-518, 1 map. January 14, 1960.

19. Records of harvest mice, Reithrodontomys, from Central America, with description of a new subspecies from Nicaragua. By Sydney Anderson and J. Knox Jones, Jr. Pp. 519-529. January 14, 1960.

20. Small carnivores from San Josecito Cave (Pleistocene), Nuevo León, México. By E. Raymond Hall. Pp. 531-538, 1 figure in text. January 14, 1960.

21. Pleistocene pocket gophers from San Josecito Cave, Nuevo León, México. By Robert J. Russell. Pp. 539-548, 1 figure in text. January 14, 1960.

22. Review of the insectivores of Korea. By J. Knox Jones, Jr., and David H. Johnson. Pp. 549-578. February 23, 1960.

23. Speciation and evolution of the pygmy mice, genus Baiomys. By Robert L. Packard. Pp. 579-670, 4 plates, 12 figures in text. June 16, 1960.

Index Pp. 671-690.

Vol. 10. 1. Studies of birds killed in nocturnal migration. By Harrison B. Tordoff and Robert M. Mengel. Pp. 1-44, 6 figures in text, 2 tables. September 12, 1956.

2. Comparative breeding behavior of Ammospiza caudacuta and A. maritima. By Glen E. Woolfenden. Pp. 45-75, 6 plates, 1 figure. December 20, 1956.

3. The forest habitat of the University of Kansas Natural History Reservation. By Henry S. Fitch and Ronald R. McGregor. Pp. 77-127, 2 plates, 7 figures in text, 4 tables. December 31, 1956.

4. Aspects of reproduction and development in the prairie vole (Microtus ochrogaster). By Henry S. Fitch. Pp. 129-161, 8 figures in text, 4 tables. December 19, 1957.

5. Birds found on the Arctic slope of northern Alaska. By James W. Bee. Pp. 163-211, pls. 9-10, 1 figure in text. March 12, 1958.

6. The wood rats of Colorado: distribution and ecology. By Robert B. Finley, Jr. Pp. 213-552, 34 plates, 8 figures in text, 35 tables. November 7, 1958.

7. Home ranges and movements of the eastern cottontail in Kansas. By Donald W. Janes. Pp. 553-572, 4 plates, 3 figures in text. May 4, 1959.

8. Natural history of the salamander, Aneides hardyi. By Richard F. Johnston and Schad Gerhard. Pp. 573-585. October 8, 1959.

9. A new subspecies of lizard, Cnemidophorus sacki, from Michoacán, México. By William E. Duellman. Pp. 587-598, 2 figures in text. May 2, 1960.

10. A taxonomic study of the Middle American Snake, Pituophis deppei. By William E. Duellman. Pp. 599-610, 1 plate, 1 figure in text. May 2, 1960.

Index Pp. 611-626.

Vol. 11. 1. The systematic status of the colubrid snake, Leptodeira discolor Günther. By William E. Duellman. Pp. 1-9, 4 figs. July 14, 1958.

2. Natural history of the six-lined racerunner, Cnemidophorus sexlineatus. By Henry S. Fitch. Pp. 11-62, 9 figs., 9 tables. September 19, 1958.

3. Home ranges, territories, and seasonal movements of vertebrates of the Natural History Reservation. By Henry S. Fitch. Pp. 63-326, 6 plates, 24 figures in text, 3 tables. December 12, 1958.

4. A new snake of the genus Geophis from Chihuahua, Mexico. By John M. Legler. Pp. 327-334, 2 figures in text. January 28, 1959.

5. A new tortoise, genus Gopherus, from north-central Mexico. By John M. Legler. Pp. 335-343. April 24, 1959.

6. Fishes of Chautauqua, Cowley and Elk counties, Kansas. By Artie L. Metcalf. Pp. 345-400, 2 plates, 2 figures in text, 10 tables. May 6, 1959.

7. Fishes of the Big Blue River Basin, Kansas. By W. L. Minckley. Pp. 401-442, 2 plates, 4 figures in text, 5 tables. May 8, 1959.

8. Birds from Coahuila, México. By Emil K. Urban. Pp. 443-516. August 1, 1959.

9. Description of a new softshell turtle from the southeastern United States. By Robert G. Webb. Pp. 517-525, 2 pls., 1 figure in text, August 14, 1959.

10. Natural history of the ornate box turtle, Terrapene ornata ornata Agassiz. By John M. Legler. Pp. 527-669, 16 pls., 29 figures in text. March 7, 1960.

Index will follow.

Vol. 12. 1. Functional morphology of three bats: Eumops, Myotis, Macrotus. By Terry A. Vaughan. Pp. 1-153, 4 plates, 24 figures in text, July 8, 1959.

2. The ancestry of modern Amphibia: a review of the evidence. By Theodore H. Eaton, Jr. Pp. 155-180, 10 figures in text. July 10, 1959.

3. The baculum in microtine rodents. By Sydney Anderson. Pp. 181-216, 49 figures in text. February 19, 1960.

4. A new order of fishlike Amphibia from the Pennsylvanian of Kansas. By Theodore H. Eaton, Jr., and Peggy Lou Stewart. Pp. 217-240, 12 figures in text. May 2, 1960.

More numbers will appear in volume 12.

Vol. 13. 1. Five natural hybrid combinations in minnows (Cyprinidae). By Frank B. Cross and W. L. Minckley. Pp. 1-18. June 1, 1960.

2. A distributional study of the amphibians of the isthmus of Tehuantepec, México. By William E. Duellman. Pp. 19-72, pls. 1-8, 3 figs. August 16, 1960.

More numbers will appear in volume 13.

* * * * *

Transcriber's Notes

Page 26: Changed "19. Cosaleacaque" to "19. Cosoleacaque".

Page 30: Changed "Brysonima crassifolia" to "Byrsonima crassifolia".

Page 34: Changed "long. 95' 29°;" to "long. 95° 29';".

Page 35: Changed "Matías Romera" to "Matías Romero".

Page 47: Changed "kown" to "known".

Pages 50 and 59: Changed "axills" to "axils".

Plate 1, Fig. 2: Changed "Veracuz" to "Veracruz".

Page 53: Changed "valadity" to "validity".

Page 61, Table 1: Changed male symbol to "(Male)" (plain text version).

Page 67: Changed "refering" to "referring".

Page 68: Changed "survided" to "survived".

Page 71: Changed "subhimid" to "subhumid" and "Amerca" to "America".

Moved University of Kansas Publications list to end of report. Vol. 9, No. 12: Changed pages from "363-387" to "363-384". Vol. 10, No. 10: Changed pages from "599-612" to "599-610".