mi. NE Zamorina (Hooper, 1953:4); Altamira (Nelson,

1898:147).

=Sciurus alleni= Nelson

Allen's Squirrel

1898. _Sciurus alleni_ Nelson, Proc. Biol. Soc. Washington, 12:147, June 3, type from Monterrey, Nuevo León.

_Distribution in Tamaulipas._--Along Sierra Madre Oriental in southwestern part of state.

This squirrel occurs in stands of oak and "nogalillos" (hickory) trees that grow along streams and arroyos. Individuals are active from sunrise to about 10:00 a. m. and again late in the afternoon. They give a soft "chirring" call.

Nelson (1899:92) noted that specimens from Miquihuana were smaller than those from the type locality. Among specimens I have examined, some are as large as topotypes and two females are larger (total length, 486 and 490) than measurements given for the species by Nelson (_op. cit._).

_Record of occurrence._--Specimens examined, 11, from Joya Verde, 35 km. SW Cd. Victoria, 3800 ft.

Additional records: Near Victoria (Nelson, 1899:92); Miquihuana (_ibid._); Joya de Salas (Goodwin, 1954:8).

=Glaucomys volans herreranus= Goldman

Southern Flying Squirrel

1936. _Glaucomys volans herreranus_ Goldman, Jour. Washington Acad. Sci., 26:463, November 15, type from Mts. of Veracruz.

_Distribution in Tamaulipas._--Known only from Aserradero del Infernillo (Goodwin, 1954:9 and 1961:9).

=Geomys personatus personatus= True

Texas Pocket Gopher

1889. _Geomys personatus_ True, Proc. U. S. Nat. Mus., 11:159 for 1888, January 5, type from Padre Island, Cameron County, Texas.

_Distribution in Tamaulipas._--Known only from the barrier beach in northeastern part of state.

The specimens examined are referred, tentatively, to _Geomys personatus personatus_ on geographic grounds. They average smaller in all measurements than _personatus_ (but are larger than _G. p. megapotamus_), do not have the sagittal crest that usually is present in _personatus_, and the shape of the pterygoid bones is distinctive. In _personatus_ and _megapotamus_ the ventral border of the pterygoids (in lateral view) is convex instead of nearly straight as in specimens from the barrier beach. The specimens recorded here are all that are known of _G. personatus_ (see account of _G. tropicalis_) from México.

_Measurements._--Average and extreme external measurements of five females from 73 miles south of Washington Beach are as follows: 266.8 (263-271); 94.8 (91-98); 34 (33-35). Cranial measurements of two males (89038, 89032) and average and extremes of five females are respectively: basal length, 49.1, 46.6, 45.9 (44.2-46.8); basilar length, 42.9, 40.0, 39.8 (38.0-40.8); zygomatic breadth, 29.6, 28.3, 28.0 (25.7-29.9); squamosal breadth, 27.8, 25.9, 26.2 (23.8-25.4); interorbital constriction, 7.4, 6.9, 7.3 (6.7-7.8); alveolar length of maxillary tooth-row, 10.3, 9.2, 9.4 (9.1-9.7).

_Records of occurrence._--Specimens examined, 17: 35 mi. SSE Matamoros, 8; 33 mi. S Washington Beach, 1; 73 mi. S Washington Beach, 8.

Additional record: 4 mi. S Washington Beach (Selander _et al._, 1962:335--possibly fragmentary skeletal remains never catalogued in any research collection).

=Geomys tropicalis= Goldman

Tropical Pocket Gopher

1915. _Geomys personatus tropicalis_ Goldman, Proc. Biol. Soc. Washington, 28:134, June 29, type from Altamira, Tamaulipas.

_Distribution in Tamaulipas._--Known only from vicinity of type locality, in southeastern part of state.

_Geomys tropicalis_ was named as a subspecies of _G. personatus_ in 1915 by E. A. Goldman. To my knowledge, no one other than Goldman has critically studied specimens of this pocket gopher, nor have specimens other than those listed in the original description been reported up to now. In 1953, Gerd H. Heinrich collected a series of 19 individuals one mile south of Altamira. These specimens were compared (by E. R. Hall in March, 1962) with the holotype and paratypes of _G. p. tropicalis_ and were found to be indistinguishable.

Careful comparisons of the specimens from one mile south of Altamira with topotypes of _G. personatus personatus_ (and specimens of other subspecies) indicate that _tropicalis_ differs from _personatus_ in a number of important characters, some of which _tropicalis_ shares with _Geomys arenarius_ of the Rio Grande Valley and adjacent areas in Texas, New Mexico, and Chihuahua (see Table 2).

TABLE 2.--DIFFERENCES BETWEEN THREE SPECIES OF GEOMYS.

=========================+==============+===============+============== |_G. arenarius_|_G. personatus_|_G. tropicalis_ -------------------------+--------------+---------------+-------------- Zygomatic arches | parallel | narrower | narrower | | posteriorly | posteriorly Sagittal crest | absent | present | small Squamosal knob | present | absent | present Interparietal | subquadrant | triangular | triangular Mesopterygoid fossa | V-shaped | U-shaped | V-shaped Ratio, zygomatic breadth | | | to basal length | 63.7-66.6 | 66.3-67.2 | 60.8-66.2 Ratio, mastoid breadth | | | to basal length | 58.0-60.4 | 59.8-63.1 | 58.0-59.6 Border of premaxilla at | | | incisive foramina | wedge-shaped | subquadrate | subquadrate -------------------------+--------------+---------------+--------------

As can be seen in the accompanying table _tropicalis_ resembles _arenarius_ in half of the eight characters considered, especially in the presence of a knob on the zygomatic process of the squamosal (the diagnostic character of _arenarius_ according to Merriam, 1895:140) and in the shape of the mesopterygoid fossa. _G. tropicalis_ differs from _arenarius_ principally in having a low sagittal crest in adult males (lacking in _arenarius_) and in the shape of the interparietal bone, which in _tropicalis_ is small (in some skulls difficult to see) and triangular instead of being relatively large and subquadrate as in _arenarius_.

_G. tropicalis_ resembles _personatus_ in half of the characters considered, notably in shape of the interparietal bone, outline of zygomatic arches, and constriction of the premaxillae where they border the incisive foramina.

Considering the distinctive combination of characters possessed by _tropicalis_, and its isolated, restricted geographic range (the nearest known record of _Geomys_ is approximately 165 miles to the north), _tropicalis_ is here regarded as a full species. A skull alone examined from 10 miles northwest of Tampico does not differ from those of other specimens studied.

The average weight of five non-pregnant July-taken females was 189.4 (180-200) grams. Weights of three males were 280, 270, and 255 grams. Females are in all measurements smaller than males.

_Measurements._--Average and extreme measurements of five females and three males from one mile south of Altamira are, respectively, as follows: 243.5 (235-250), 260, 260, 265; 82.0 (78-85), 87, 93, 89; 32.2 (31-33), 35, 35, 33; ear from notch in both sexes, 5; condylobasal length, 42.3 (41.3-43.1), 46.0, 48.0, 46.2; zygomatic breadth, 26.6 (25.1-27.7), 30.4, 31.2, 30.5; interorbital constriction, 6.2 (6.1-6.3), 6.0, 6.2, 6.3; length of nasals, 14.6 (14.0-15.3), 17.0, 16.8, 15.9; alveolar length of maxillary tooth-row, 9.0 (8.6-9.3), 9.9, 10.0, 9.4.

_Records of occurrence._--Specimens examined, 19: 1 mi. S Altamira, 18; 10 mi. NW Tampico, 1.

Additional record: Altamira (Goldman, 1915:134).

=Heterogeomys hispidus negatus= Goodwin

Hispid Pocket Gopher

1953. _Heterogeomys hispidus negatus_ Goodwin, Amer. Mus. Novit., 1620:1, May 4, type from Gómez Feras [Farías], 1300 ft., Tamaulipas.

_Distribution in Tamaulipas._--Known only from the vicinity of the type locality.

Specimens of this pocket gopher were taken in large Macabee traps, at night with the aid of a dog, and by natives using slingshots. Mounds of _H. hispidus_ were common two miles west of El Carrizo near banana trees; the mouths of burrows were four to five inches in diameter. Two females collected at this locality on April 16 and 17 were lactating.

Specimens examined of _H. hispidus_ from Tamaulipas resemble the description of _H. h. negatus_ more than that of _H. h. concavus_, and are referred, therefore, to _negatus_. I assume, on geographic grounds, that the individuals reported by Hooper (1953:5) as _concavus_ are _negatus_; they are here referred to as _negatus_. If this referral is correct, the subspecies _concavus_ probably does not occur in Tamaulipas.

_Records of occurrence._--Specimens examined, 6: Ejido Santa Isabel, 2 km. W Pan-American Highway, 2000 ft., 1; 2 km. W El Carrizo, 1; 5 km. W El Carrizo, 4.

Additional records: Rancho Pano Ayuctle (Hooper, 1953:5); Gómez Farías (Goodwin, 1953:1).

=Cratogeomys castanops=

Yellow-faced Pocket Gopher

Two subspecies of _Cratogeomys castanops_ occur in Tamaulipas, _C. c. planifrons_ in the higher elevations of the Sierra Madre Oriental in the western part of the state, and _C. c. tamaulipensis_ on the plains of the Río Grande.

Specimens from Miquihuana were trapped in tunnels at 6400 feet elevation. At Palmillas, individuals were trapped in an area of mesquite, other bushes and "lechuguilla." Three specimens from southeast of Reynosa were collected in traps set along the dikes of irrigation ditches. Most specimens from Nicolás were brought by natives to the collector, but some were caught in traps set in tunnels among the desert bushes.

=Cratogeomys castanops planifrons= Nelson and Goldman

1943. _Cratogeomys castanops planifrons_ Nelson and Goldman, Proc. Biol. Soc. Washington, 47:146, June 13, type from Miquihuana, 5000 ft., Tamaulipas.

_Distribution in Tamaulipas._--Higher elevations in southwestern part of state.

Specimens from four miles north of Jaumave do not differ from specimens from Miquihuana. The weights of nine females averaged 146.4 (110-210) grams; three males weighed 178, 203, and 215 grams.

_Records of occurrence._--Specimens examined, 29: Miquihuana, 6400 ft., 9; 4 mi. N Jaumave, 2500 ft., 5; Nicolás, 56 km. NW Tula, 5500 ft., 15.

=Cratogeomys castanops tamaulipensis= Nelson and Goldman

1934. _Cratogeomys castanops tamaulipensis_ Nelson and Goldman, Proc. Biol. Soc. Washington, 47:141, June 13, type from Matamoros, Tamaulipas.

_Distribution in Tamaulipas._--Known only from two localities in extreme northern part of state, but probably occurs throughout northeastern part of state.

Three specimens from three miles southeast of Reynosa are referred to _C. c. tamaulipensis_ on geographic grounds. They are tawny brown dorsally instead of cinnamon brown or pinkish cinnamon as Nelson and Goldman (1943:141) described _tamaulipensis_, and the basioccipital bone (in one male) is parallel-sided instead of wedge-shaped. Possibly this difference is owing to sex; Nelson and Goldman studied only one adult, a female (the type), and the only adult seen by me was a male.

_Measurements._--An adult male (58118) from three miles southeast of Reynosa, measured as follows: 301; 81; 40; 7; condylobasal length, 57.0; zygomatic breadth, 41.2; palatal length, 36.1; breadth of rostrum, 11.8; length of nasals, 22.0; squamosal breadth, 34.0; alveolar length of maxillary tooth-row, 10.8.

_Records of occurrence._--Specimens examined, 3, from 3 mi. SE Reynosa.

Additional record: Matamoros (Nelson and Goldman, 1934:140).

=Perognathus merriami merriami= J. A. Allen

Merriam's Pocket Mouse

1892. _Perognathus merriami_ J. A. Allen, Bull. Amer. Mus. Nat. Hist., 4:45, March 25, type from Brownsville, Cameron Co., Texas.

_Distribution in Tamaulipas._--State-wide except southwestern part.

Most of the available specimens of _P. m. merriami_ were collected in the semi-arid areas of mesquite and grasses. At Soto la Marina _P. m. merriami_ was abundant in open fields surrounded by brush. One female, collected on July 4, one mile south of Altamira was lactating. Weights of 16 adults from Soto la Marina and that of nine adults from the vicinity of San Fernando are, respectively: 8.2 (7-10) and 8.1 (7-9) grams.

Specimens from Tamaulipas are darker than those examined from Coahuila and southern Texas. A skull picked up on the barrier beach, 73 miles south of Washington Beach, differs from all other skulls examined in having the rostrum (3.6 mm.) and M1 (4.3) wider, auditory bullae relatively smaller, and glenoid fossa larger (2.6 instead of less than 2.3 in specimens from Soto la Marina).

_Records of occurrence._--Specimens examined, 46: 4-4.5 mi. S Nuevo Laredo, 900 ft., 4; 10 mi. S, 11 mi. E Nuevo Laredo, 600 ft., 2; 1 mi. S Santa Teresa, 1; San Fernando, 180 ft., 1; 2 mi. W San Fernando, 180 ft., 14; 73 mi. S Washington Beach, 1; 12 mi. NW San Carlos, 1300 ft., 1; Soto la Marina, 19; Ciudad Victoria, 1; 17 mi. SW Tula, 3900 ft., 1; 1 mi. S Altamira, 1.

Additional records (Osgood, 1900:22, unless otherwise noted): Mier; Reynosa; Matamoros; 40 mi. S Matamoros (Hooper, 1953:5); Hidalgo; Altamira.

=Perognathus hispidus hispidus= Baird

Hispid Pocket Mouse

1858. _Perognathus hispidus_ Baird, Mammals, in Repts. Expl. Surv. ..., 8(1):421, July 14, type from Charco Escondido, Tamaulipas.

_Distribution in Tamaulipas._--Central and northern parts of state.

Two specimens examined from the vicinity of Nuevo Laredo were trapped in weeds and tall grass along an irrigation ditch that ran between desert and a cornfield. One was a lactating female (November 15) and weighed 31 grams; the other, an immature male, weighed 23 grams. A May-taken specimen from Soto la Marina possesses a broader and more ochraceous lateral line than the other three individuals examined from Tamaulipas and the Texan specimens seen.

_Records of occurrence._--Specimens examined, 4: 10 mi. S, 11 mi. E Nuevo Laredo, 600 ft., 2; Soto la Marina, 500 ft., 1; 9-1/2 mi. SW Padilla, 800 ft., 1.

Additional records (Osgood, 1900:44, unless otherwise noted): Mier; Matamoros; Charco Escondido (Baird, 1858:422); 3 mi. W Soto la Marina (Hooper, 1953:5).

=Perognathus nelsoni nelsoni= Merriam

Nelson's Pocket Mouse

1894. _Perognathus (Chaetodipus) nelsoni_ Merriam, Proc. Acad. Nat. Sci. Philadelphia, 46:266, September 27, type from Hacienda La Parada, about 25 mi. NW Cd. San Luis Potosí, San Luis Potosí.

_Distribution in Tamaulipas._--Known only from the west side of the Sierra Madre Oriental in southwestern part of state.

Most of the specimens examined were taken in semi-arid habitats where the dominant plants were cactus, weeds and bushes.

In Tamaulipas, specimens from the southern localities (places labeled with reference to Tula) are darker than those from the two northernmost localities (Miquihuana and four miles north of Jaumave). Most measurements are about equal in the southern and northern specimens, but in some measurements southern specimens average slightly smaller than those from the north. Greatest length of skull is a case in point. The difference in size is reflected in the weights. Average weights of nine males and nine females from southern localities are, respectively, 14.7 (12-16.5) and 13.8 (12-15.5) instead of 18.5 (17-20) and 17.0 (15-18) grams for four males and six females from the northern localities. In general, Tamaulipan specimens average somewhat smaller than those from other localities in eastern México (see measurements given by Baker, 1956:238, Dalquest, 1953:107, and Osgood, 1900:53).

_Measurements._--Average and extreme measurements of six specimens (2 males and 4 females) from Miquihuana, three males from four miles north of Jaumave, and five (3 males and 2 females) from nine miles southwest of Tula are, respectively, as follows: 176.2 (163-185), ----, 170, 173, (4 specimens only) 179.0 (165-186); 99.8 (97-105), ----, 90, 93, (4 specimens only) 96.7 (88-104); 22.5 (21-23), 23, 23, 24, 22.6 (22-23); 8 (8), 8, 8, 8, 8.8 (8-9); greatest length of skull, 26.1 (25.6-26.6), 25.8, 26.5, 26.9, 25.2 (24.9-25.7); mastoid breadth, 13.3 (12.9-13.6), 13.2, 13.8, 13.6, 13.1 (12.9-13.4); interorbital constriction, 6.4 (6.1-6.6), 5.9, 6.3, 6.3, 6.3 (6.1-6.8); interparietal breadth, 7.4 (6.8-7.9), 7.7, 7.2, 7.2, 7.6 (7.3-7.9); alveolar length of maxillary tooth-row, 3.7 (3.5-4.0); 3.6, 3.5, 3.6, 3.6 (3.5-3.8).

_Records of occurrence._--Specimens examined, 42: Miquihuana, 6300 ft., 7; 4 mi. N Jaumave, 2500 ft., 5; Nicolás, 56 km. NW Tula, 5500 ft., 10; Tajada, 23 mi. NW Tula, 5200 ft., 6; 8 mi. N Tula, 4500 ft., 1; 9 mi. SW Tula, 3900 ft., 13.

Additional record: Jaumave (Miller, 1924:284).

=Dipodomys ordii=

Ord's Kangaroo Rat

This species has a restricted geographic distribution in Tamaulipas, although three subspecies occur in the state; two of them occur in the extreme northeast and the other in the far west.

=Dipodomys ordii durranti= Setzer

1949. _Dipodomys ordii fuscus_ Setzer, Univ. Kansas Publ., Mus. Nat. Hist., 1:555, December 27, type from Jaumave, Tamaulipas.

1952. _Dipodomys ordii durranti_ Setzer, Jour. Washington Acad. Sci., 42:391, December 17, a renaming of _D. o. fuscus_ Setzer, 1949.

_Distribution in Tamaulipas._--Semi-desert areas in western part of state.

The specimen examined from four miles north of Jaumave was trapped in a xeric area in which the vegetation consisted of mesquite, high palmlike yuccas, and "lechugilla." Specimens from the vicinity of Tula were trapped along bushy fence rows and adjacent to clumps of bushes and cactus, or shot at night in an area in which the soil was a sandy loam having relatively large amounts of gravel. The average weight of seven specimens from Nicolás was 50.3 (42-60) grams.

According to Lidicker (1960:178 and in _litt._), the place called Lulú that was ascribed to Tamaulipas by Setzer (1949:550), and from which _D. o. durranti_ was reported, actually is in Zacatecas.

_Records of occurrence._--Specimens examined, 19: Miquihuana, 6200 ft., 2; 4 mi. N Jaumave, 2500 ft., 3; Nicolás, 56 km. NW Tula, 12; 8 km. N Tula, 4500 ft., 2.

Additional records (Setzer, 1949:556): Nuevo Laredo; Jaumave.

=Dipodomys ordii parvabullatus= Hall

1951. _Dipodomys ordii parvabullatus_ Hall, Univ. Kansas Publ., Mus. Nat. Hist., 5:38, October 1, type from 88 mi. S and 10 mi. W Matamoros, Tamaulipas.

_Distribution in Tamaulipas._--Known only from two islands off the barrier beach.

Weight of four adults averaged 49.2 (44-60) grams.

_Records of occurrence._--Specimens examined, 17: 33 mi. S Washington Beach, 4; 88 mi. S, 10 mi. W Matamoros, 7; 90 mi. S, 10 mi. W Matamoros, 6.

=Dipodomys ordii compactus= True

1889. _Dipodomys compactus_ True, Proc. U. S. Nat. Mus., 11:160, January 5, type from Padre Island, Cameron Co., Texas.

1942. _Dipodomys ordii compactus_, Davis, Jour. Mamm., 23:332, August 13.

_Distribution in Tamaulipas._--Reported only from Bagdad (Hall, 1951:41).

=Dipodomys merriami atronasus= Merriam

Merriam's Kangaroo Rat

1894. _Dipodomys merriami atronasus_ Merriam, Proc. Biol. Soc. Washington, 9:113, June 21, type from Hacienda La Parada, about 25 mi. NW San Luis Potosí, San Luis Potosí.

_Distribution in Tamaulipas._--Mexican Plateau in western part of state.

Specimens examined are tentatively assigned to _Dipodomys merriami atronasus_. They differ from typical _atronasus_ as pointed out by Lidicker (1960:177). He noted that individuals from the eastern edge of the range of _D. m. atronasus_ were slightly paler than typical specimens, but I found Tamaulipan material to be much darker, especially behind the nose and ears (blackish instead of brownish), than specimens from Aguascalientes, San Luis Potosí and Zacatecas.

Specimens examined were collected under the same conditions and in the same areas as _D. ordii durranti_. The average weight of 20 adults (11 females and nine males) was 46.6 (38-50) grams.

_Records of occurrences._--Specimens examined, 27: Nicolás, 56 km. NW Tula, 5500 ft., 16; Tajada, 23 mi. NW Tula, 5200 ft., 4; 15 mi. N Tula, 1; 8 mi. N Tula, 4500 ft., 3; 9 mi. SW Tula, 3900 ft., 3.

Additional record: Tula (Lidicker, 1960:178).

=Liomys irroratus=

Mexican Spiny Pocket Mouse

This species is probably the most common rodent in Tamaulipas. It was taken at almost every locality sampled and was associated with many other kinds of rodents. Its distribution is state-wide with the exception of the extreme northwestern part. Two subspecies are represented in Tamaulipas, _L. i. alleni_, which occurs in the western side of the Sierra Madre Oriental in the southwest part of the state, and _L. i. texensis_, which occupies the rest of the range of the species in the state.

At Soto la Marina specimens were taken in dense brush, around the cultivated fields; no burrows were seen and all specimens were trapped before 10:00 p.m. On the Sierra de Tamaulipas, _Liomys_ was collected in practically all microhabitats. In the vicinity of San Fernando, individuals were trapped in a dry area in which vegetation consisted of mesquite, cactus and chollas; the ground there was covered with dry leaves and small sticks, and burrows were found near the base of the mesquite bushes. One specimen was taken near the house of a woodrat. Two kilometers west of El Carrizo, where _Liomys irroratus_ is called "ratón tuza," specimens were collected on rocks inclined at an angle of about twenty-five degrees that were covered with zacatón grass and some bushes. Some individuals were taken in a sugar cane field that was surrounded by bushes and tall grass; _Baiomys taylori_, _Sigmodon hispidus_, and _Peromyscus leucopus_ were taken in the line of traps. One specimen was caught in a trap baited with banana.

Some dates concerning reproduction of _Liomys irroratus_ in Tamaulipas are as follows: La Pesca, May 25, one female lactating and one female pregnant with 4 embryos that measured 8 mm.; Jaumave, July 26-29, three females lactating and three pregnant females that carried 6 embryos (6 mm.), 6 embryos (15 mm.), and 5 embryos (15 mm.); Palmillas, July 23, a female with 1 embryo measuring 6 mm.; Nicolás, October 19, a female carrying 4 embryos measuring 3 mm.

=Liomys irroratus alleni= (Coues)

1881. _Heteromys alleni_ Coues, Bull. Mus. Comp. Zool., 8:187, March, type from Río Verde, San Luis Potosí.

1911. _Liomys irroratus alleni_, Goldman, N. Amer. Fauna, 34:56, September 7.

_Distribution in Tamaulipas._--Extreme southwestern part of state.

This subspecies is easily distinguished from _L. i. texensis_ by the following features: hind foot larger, 31.5 (30-33.5) instead of 27.8 (27-29); skull longer, 34.2 (32.4-36.4) instead of 31.5 (30.0-32.5); maxillary tooth-row longer, 5.4 (5.0-5.8) instead of 5.0 (4.8-5.1); interorbital constriction relatively narrower in _alleni_. Intergradation between _L. i. alleni_ and _L. i. texensis_ takes place at Rancho Santa Rosa (where, of the two specimens, one is conspicuously larger than the other), eight kilometers northeast of Antiguo Morelos, El Encino, and Ejido Santa Isabel. All specimens from the localities mentioned are here assigned to _texensis_.

Weight of three pregnant females averaged 68.9 (64-78) grams, that of non-pregnant females, 65.6 (64-68), and that of six males 73.0 (65-80).

_Records of occurrence._--Specimens examined, 34: Villa Mainero, 1700 ft., 2; Nicolás, 56 km. NW Tula, 5500 ft., 6; Jaumave, 2400 ft., 23; 16 mi. N, 6 mi. W Palmillas, 5500 ft., 1; 14 mi. N, 6 mi. W Palmillas, 5500 ft., 2.

Additional records: Miquihuana (Goldman, 1911:56); Tula (Hooper and Handley, 1958:18).

=Liomys irroratus texensis= Merriam

1902. _Liomys texensis_ Merriam, Proc. Biol. Soc. Washington, 15:44, March 5, type from Brownsville, Cameron Co., Texas.

1911. _Liomys irroratus texensis_, Goldman, N. Amer. Fauna, 34:59, September 7.

_Distribution in Tamaulipas._--State-wide except extreme southwestern and northwestern parts.

Intergradation occurs between _L. i. texensis_ and _L. i. pretiosus_ in southeastern Tamaulipas as noted previously by Hooper (1953:5). Individuals from Altamira and one mile south thereof are small and dark as in _pretiosus_, but cranial measurements are as in _texensis_ to which they are here assigned. Specimens from the vicinity of Tampico are typical _texensis_.

Average weight of the specimens from three different localities are as follows: Soto la Marina, seven males, 42.7, 14 females, 36.9; Sierra de Tamaulipas, 12 males, 47.3, 20 females, 40.7; Sierra Madre Oriental, eight males, 45.5, nine females, 37.0 grams.

The specimens reported by Ingles (1959:394) from two miles south of El Mante as _L. irroratus_ are here referred to _texensis_ on geographic grounds.

_Records of occurrence._--Specimens examined, 121: 7 km. S, 2 km. W San Fernando, 7; 7 km. SW La Purisima, 1; Rancho Santa Rosa, 25 km. N, 13 km. W Cd. Victoria, 260 m., 2; 36 km. N, 10 km. W Cd. Victoria, 1; 15 mi. N Cd. Victoria, 2; 4