Part 63

ARMIL´LA, _n._ Ring of color, like a bracelet, around lower end of crus.

ARM´PIT, _n._ (78.) See AXILLA.

ARTE´RIAL, _a._ Pertaining to arteries; as, arterial system, arterial blood.

AR´TERY, _n._ Vessel conveying blood from the heart.

ARTICULA´TION, _n._ A joining together; joint.

ARTIC´ULUS, _n._ Joint of a finger or toe (commonly used to signify the hinge itself, but better to designate any one of the segments joined by articulation).

ARTIFI´CIAL, _a._ Elaborate; skilfully or artfully contrived. Some birds build highly _artificial_ nests. Also, arbitrary; as, an _artificial_ classification, more or less at variance with that which a _natural_ system may be.

AR´TUS, _n._; pl. _artus_. Any member, limb.

ARYT´ENOID, _a._ Denoting certain ossicles of the larynx.

ASCAR´IDES, _n. pl._ Certain intestinal parasites.

ASH _or_ ASH´Y, _a._ Pale gray.

ASTER´NAL (_ribs_), _a._ Denoting “floating” ribs; those not joining the sternum.

ASTRAG´ALUS, _n._ One of two proximal tarsal bones of birds, early confluent with the tibia.

ASYMMET´RICAL, _a._ Uneven; disproportionate as to opposite, as right and left, parts.

ASYM´METRY, _n._ Disproportion of duplicate parts or organs, or of those which are repeated on opposite sides of a plane or axis.

AT´AVISM, _n._ Reversion, or tendency to revert, to characters of ancestral stock.

AT´LAS, _n._ First cervical vertebra, articulating with the occipital bone.

ATRES´IA, _n._ Closure.

AT´ROPHY, _n._ See HYPERTROPHY.

ATTEN´UATE, _a._ Growing gradually slenderer toward an extremity; or, narrowly produced for a long distance; in neither case necessarily sharp-pointed, which would be rather _acuminate_.

ATTYP´ICAL, _a._ Of particular character acquired in specialization from a common type.

AUCHE´NIUM, _n._ Lower back part of neck; the scruff. (50.) (Little used.)

AU´RAL or AURIC´ULAR, _a._ Pertaining to the ear.

AU´RICLE, _n._ The external ear; wanting or imperfect in birds. Also, cavity (right and left) of the heart receiving blood from the system and lungs; also called _atrium_.

AURIC´ULARS, _n. pl._ Peculiar feathers overlying the ear-opening.

AUTOCH´THONOUS, _a._ Indigenous.

AUTOG´ENOUS, _a._ Literally, self-producing. In homology, developing from distinct and independent centres. Opposed to _exogenous_.

AU´TOPSY, _n._ Personal observation or examination.

AUTOP´TICAL, _a._ Personally inspected.

AUTUM´NAL PLUM´AGE. That ensuing from the first moult, if any, or prior to the spring moult, from which it is different in many birds.

A´VIARY, _n._ Place where birds are kept captive.

AVIC´ULA, _n._ Little bird; hence, nestling, fledgling, or any ungrown bird.

AVICUL´TURE, n. Care of birds.

A´VIS, _n._; pl. _aves_. Bird.

AXIL´LA, _n._ Armpit; hollow beneath the shoulder. (78.)

AX´ILLAR or AX´ILLARY, _a._ Pertaining to the armpit.

AX´ILLARIES, _n. pl._ Lengthened or otherwise distinguished feathers growing from the axillary region. (81.)

AX´IS, _n._ Second cervical vertebra. Also, an imaginary line passing along the middle of any one of the three mutually perpendicular planes of the body, the longitudinal, vertical, and transverse. Also, a pivot.

A´ZYGOS, _a._ Single, in the sense of _not paired_.

B.

BACK, _n._ Upper surface of body proper, corresponding to dorsal and sacral vertebræ. Includes INTERSCAPILIUM and TERGUM (which see). (57.)

BACK OF NECK. Cervical region. Includes NUCHA and CERVIX (which see). Equivalent to hind-neck. (48.)

BACK OF TAR´SUS. Hinder edge and hinder half, on each side, of tarsus. See PLANTA. Homologically the sole. (106.)

BAND or BAR. Any crosswise color-mark, transverse to long axis of the body.

BAND´ED or BARRED, _a._ Marked crosswise.

BARB, _n._ Any one of the laminæ composing the vane of a feather.

BAR´BA, _n._ Beard. Lengthened or otherwise distinguished feathers of chin or throat.

BARBAT´US, _a._ Bearded.

BAR´BICEL, _n._ Barb of a barbule, not hooked. Compare HAMULUS.

BAR´BULE, _n._ Barb of a barb. (148.)

BA´SAL, _a._ Pertaining to the base; situate at the base.

BASE, BA´SIS, _n._ Bottom; root; origin.

BASIHY´OID, n. Central tongue-bone.

BASIOCCIP´ITAL, _n._ Basal element of the occipital bone; centrum of hindermost cranial vertebra.

BASIPTER´YGOID, _n._ A boss or protuberance of the base of the sphenoid bone, often movably abutting against the pterygoid bone.

BASISPHE´NOID, _n._ Basal element of sphenoid bone; centrum of second cranial vertebra.

BEAK, _n._ Bill. See ROSTRUM. (9.)

BEL´LY, _n._ See ABDOMEN. (65.)

BELT, _n._ Bar or band of color more or less completely encircling the body.

BEND OF WING. Angle or prominence formed at carpus in the folded wing.

BEV´ELLED, _a._ Having two plane surfaces meeting obliquely.

BEV´Y, _n._ Flock of quail.

BI- (_in composition_). Twice; double.

BIBLIOG´RAPHY, _n._ History or other account of the literature of the subject.

BI´CEPS, _n._ Principal flexor muscle of forearm.

BI´NARY, _a._ Double, in sense of compounded of two.

BINO´MIAL, _a._ Of two terms. Also, noting a system of nomenclature in which each object has two names, generic and specific. This is the generally adopted system at present.

BIOL´OGY, _n._ The study of living beings, as to the laws and results of organization. It is more comprehensive than physiology.

BIOTAX´Y, _n._ Equivalent to taxonomy.

BIVEN´TER, _n._ Name of a double-bellied muscle of the neck.

BLAS´TODERM, _n._ Superficies of the early embryo.

BOAT-SHAPED (_tail_), _a._ Having plane of each side of tail meeting the other obliquely, making a re-entrance above and keel below.

BOOT, _n._ The tarsal envelope when entire.

BOOT´ED (_tarsus_), _a._ Having the tarsal envelope entire, i.e. undivided in most or all of its extent, by fusion of the usual scales or plates. (111.)

BO´REAL, _a._ Northern.

BOSS, _n._ Stud; knob; protuberance; short stout process.

BRACH´IAL, _a._ Pertaining to the wing.

BRACHYP´TEROUS, _a._ Short-winged.

BRACHYU´ROUS, _a._ Short-tailed.

BREAST, _n._ (62.) See PECTUS.

BRIS´TLE, _n._ Small stiff hair-like feather, especially about the mouth or eyes. Compare VIBRISSA.

BRON´CHIAL, _a._ Pertaining to the bronchi.

BRON´CHUS, _n._; pl. _bronchi_. Fork or branch of the windpipe below, leading to either lung.

BUC´CAL, _a._ Pertaining to the cheeks internally.

BUFF, BUFFY; _a._ Pale brownish-yellow; color of yellow buckskin.

C.

CADU´COUS, _a._ Falling off early.

CÆ´CAL, _a._ Pertaining to the cæca.

CÆ´CUM, _n._; pl. _cæca_. (Pronounced _see´cum_.) Intestinal cul-de-sac at junction of smaller and larger intestines, usually present paired in birds; sometimes a foot long. (Also written _cœcum_, _cœca_.)

CAL´AMUS, _n._ Quill; the dry, hard, horny portion of the stem of a feather below the web, hollow or partly pithy, and translucent. Calamus + rhachis = scapus. (145.)

CALCA´NEAL, _a._ Pertaining to the back upper portion of the tarso-metatarsus (tarsus of ordinary language).

CALCA´NEUM, _n._ Heel; back upper part of tarso-metatarsus. Same as _talus_. (107.) One of the tibial condyles is by some regarded as the homologue of the calcaneum.

CAL´CAR, _n._ Spur; sharp horn-covered bone-cored process on the shank of many birds; also, similar horny process on the metacarpal bone.

CALCARAT´US, _a._ Spurred.

CALCA´REOUS, _a._ Chalky. A cormorant’s egg is covered with _calcareous_ substance.

CALCIF´IC, _a._ Calcifying; an epithet of that portion of the oviduct where the egg-shell is formed.

CALIG´ULA, _n._ Same as BOOT (which see).

CAL´LUS, _n._ New bony matter joining a fracture.

CALYPTE´RIA, _n. pl._ Tail-coverts; the smaller feathers underlying or overlying the base of the tail. (Little used.) See CRISSUM and TECTRICES CAUDÆ. (71.)

CA´LYX, _n._ Pedicellated ovarian capsule of two membranes with lax tissue and vessels, rupturing at a point called the _stigma_ to discharge the ovum, then collapsing and becoming absorbed.

CAMPTE´RIUM, _n._ Front and outer border of wing as far as the bone extends. (Little used.) (95.)

CANALIC´ULUM, _n._ Little groove.

CAN´CELLATED, _a._ Denoting bony network.

CAN´THUS, _n._; pl. _canthi_. Corner of eye where the lids meet; commissural point of eyelids. _Canthi_ are anterior and posterior.

CAP, _n._ PILEUS (which see). (30.)

CAP´ILLARY, _a._ or _n._ Of hair-like slenderness. The smallest bloodvessels are the capillaries.

CAPIS´TRATE, _a._ Hooded or cowled.

CAPIS´TRUM, _n._ Hood or cowl; front of head all around bill. (38.)

CAP´ITATE, _a._ Said of a feather having enlarged extremity.

CAPIT´ULUM, _n._ Head of a rib.

CAP´SULAR, _a._ Denoting certain ligaments that completely invest a joint.

CA´PUT, _n._; gen. _capitis_, pl. _capita_. Head. (9, 29.)

CAR´DIAC, _a._ Pertaining to the heart.

CARI´NA, _n._ Keel; under ridge, as if a keel.

CAR´INATE, _a._ Keeled; ridged beneath as if keeled; having a keel, as the sternum of most birds.

CAR´INATE (_birds_), _n._ Those possessing a keeled sternum; the group _Carinatæ_ as contrasted with _Ratitæ_.

CAR´NEOUS, _a._ Fleshy.

CARNIV´OROUS, _a._ Flesh-eating.

CAROT´ID (_artery_), _a._ for _n._ The principal bloodvessel of the neck, single in most birds, sometimes paired as in mammalia.

CAR´PAL, _a._ Pertaining to the wrist.

CAR´PAL AN´GLE, _n._ Prominence formed at the wrist-joint when the wing is closed. It is practically an important point regionally, since the universally used measurement, “length of wing,” is from this point to the end of the longest quill.

CAR´PUS, _n._ The wrist; especially its bones.

CAR´TILAGE, _n._ A whitish, hard, and solid, but elastic, flexible, and soluble, substance of the body, permanent, or becoming osseous by deposition of bone-earth. It occurs in the windpipe, in many joints, and elsewhere.

CARTILAG´INOUS, _a._ Like, containing, or consisting of, cartilage.

CAR´UNCLE, _n._ Small fleshy excrescence, particularly about the head, usually naked, and wrinkled, warty, or brightly colored.

CARUN´CULATE, _a._ Having caruncles.

CAU´DA, _n._ The tail. (69.) In descriptive ornithology, generally only the tail-feathers are meant. _Cauda navicularis_ = BOAT-SHAPED TAIL (which see).

CAU´DAD. Backwards; toward the tail.

CAU´DAL, _a._ Pertaining to the tail; as, _caudal_ vertebræ, or _caudal_ extremity; but we hardly say _caudal_ feathers.

CELL, _n._ Any closed sac containing fluid or other substance.

CEL´LULAR, _a._ Having cells; composed of cells.

CEN´TRE OF GRAV´ITY, _n._ Point of a body about which the whole is balanced, and which, if supported, supports the whole. In a flying bird the centre of gravity is below the middle of the body, so that the bird is naturally ballasted.

CEN´TRUM, _n._; pl. _centra_. Body of a vertebra.

CEPH´ALAD. Forwards; towards the head.

CEPHAL´IC, _a._ Pertaining to the head.

CEPHALO-CER´CAL (_axis_), _a._ Denoting the long axis of the body.

CE´RA, CERE, CERO´MA, _n._ Fleshy, cutaneous or membranous, often feathered, covering of base of bill of many birds, as parrots, hawks, and owls; differing thus in texture from the rest of the _rhamphotheca_, and usually also showing an evident line of demarcation. When present, the nostrils are always pierced in its substance,—at least at its edge.

CERATOHY´AL, _n._ A portion of the “horn” of the hyoid bone.

CER´CAL, _a._ Pertaining to the tail. (Little used.)

CEREBEL´LAR, _a._ Pertaining to the cerebellum.

CEREBEL´LUM, _n._ Little brain; the hinder, lower, smaller mass of the brain, in birds striate transversely.

CER´EBRAL, _a._ Pertaining to the brain.

CER´EBRO-SPINAL (_axis or column_). The whole neural axis, or column of nerve-substance enclosed in the spinal canal and cranium.

CER´EBRUM, _n._ Brain proper, or larger brain, as distinguished from the _cerebellum_.

CERU´MEN, _n._ Ear-wax.

CER´VICAL, _a._ Pertaining to the hind-neck; as, a _cervical_ collar. Also, pertaining to the whole neck; as, _cervical_ vertebræ.

CER´VIX, _n._ Hind-neck; from occiput to interscapulium, including nape and scruff. (48.)

CHALAZ´Æ, _n. pl._ Twisted filaments of condensed albumen forming a thread at each pole of the yolk, steadying it by attachment to the lining membrane of the egg, and balancing it in such manner that the “tread” stays uppermost.

CHALAZIF´EROUS, _a._ Denoting the layers of condensed albumen which form the chalazæ.

CHAR´ACTER, _n._ Any material attribute susceptible of definition for use in description and classification. Also, a sum of such attributes; as, of passerine _character_.

CHAS´MA, _n._ Decussation of the optic nerve.

CHEEK, _n._ Outside of base of lower jaw; also, the corresponding region of upper jaw. Compare GENÆ and MALAR REGION. (26.) (The term is differently employed by various writers, and is at best not definite.)

CHIN, _n._ Space between forks of lower jaw; upper throat. See MENTUM. (46.)

CHO´ROID, _n._ Vascular black membrane of the eye, between retina and sclerotic. _Choroid plexus_, a certain fold of the _pia mater_.

CHYLE, _n._ A certain intestinal fluid resulting from digestion.

CHYME, _n._ A certain product of incompleted digestion.

CICATRIC´ULA, _n._ Dark spot on the surface of a fecundated yolk. See YOLK.

CIL´IATED, _a._ Bristly; furnished with bristles, or small bristle-like feathers; fringed.

CIL´IUM, _n._; pl. _cilia_. Bristly or hair-like feather, about the mouth and eyes especially. See VIBRISSA and SETA.

CINE´REOUS, _a._ Of an ashy color.

CIRCUM- (_in composition_). Around; about: as, _circumanal_, _circumorbital_, _circumaural_,—around the anus, orbit, ear, etc.

CIRCUMDUC´TION, _n._ Movement of a limb by which, if completed, a cone is described.

CIRRH´OUS, _a._ Tufted.

CLASS, _n._ Fundamental division of animals: the _class_ of Birds; the _class Aves_.

CLASSIFICA´TION, _n._ Systematic arrangement.

CLAV´ICLE, _n._ Collar-bone. In birds, the two clavicles usually unite to form the furculum, merry-thought or wish-bone.

CLAVIC´ULAR, _a._ Pertaining to the clavicles.

CLAW, _n._ (121.)

CLAW-JOINT, _n._ (122.) See RHIZONYCHIUM.

CLIT´ORIS, _n._ Erectile venereal organ of the female, homologue of the male penis, present in some birds.

CLOA´CA, _n._ Enlarged lower end of straight gut, receptacle of products of genito-urinary system and refuse of digestion.

CLUTCH, _n._ Nest-complement of eggs.

CNE´MIAL, _a._ Pertaining to the crus or shin. Equivalent to _crural_.

CNEMID´IUM, _n._ End of crus, naked in most wading birds.

COCCYGE´AL, _a._ Pertaining to the tail, especially to its bones; synonymous with _caudal_.

COC´CYX, _n._ The tail, as to its bones collectively. _Os coccygis._ Any one of the tail-bones, or coccygeal vertebræ.

COCH´LEA, _n._ A certain portion of the inner ear.

CŒ´CUM, _n._; pl. _cœca_. See CÆCUM.

CŒ´LIAC, _a._ Pertaining to certain of the abdominal viscera. Little used, excepting as the name of a certain artery, the _cœliac axis_.

COI´TUS, _n._ Sexual intercourse.

COL´LAR, _n._ Ring of color around neck. See TORQUES. (55.)

COL´LUM, _n._ Neck; part of body between and connecting head and trunk. (47.)

COLORA´TION, _n._ Coloring; pattern or mode of coloring, or the colors collectively.

COLUMEL´LA, _n._ Bone or cartilage of the inner ear of _Sauropsida_, answering to the _stapes_ of mammalia.

COMB, _n._ Erect fleshy lengthwise process, or caruncle, on top of head, as in the domestic cock.

COMMIS´SURAL POINT. Point where the apposed edges of the mandibles meet and join; corner of the mouth. Equivalent to angle of the mouth, _angulus oris_.

COM´MISSURE, _n._ (Lat. _con_ and _mitto_, to put or lay together.) Line of closure of the two mandibles; track or trace of their apposed edges when the jaws are closed. Often improperly used to signify the _opening between_ the mandibles; but this is _apertura oris_, _gape_, _rictus_. _Commissure_ is the whole _rima oris_, outline of the mouth, when such outline of upper and under jaw is made one in closure of the mouth.

COMPLEX´US, _n._ Name of a certain cervical muscle.

COMPRESSED´, _a._ Narrowed sidewise; higher than wide. The opposite of _depressed_.

COMPRESSED´ (_tail_), _a._ Folded together, as in the barnyard cock. = _Cauda compressa_.

CONA´RIUM, _n._ Same as PINEAL BODY (which see).

CON´CAVE, _a._ Hollowed, as the inner side of a curved line or inner face of a curved surface. Opposite of _convex_.

CON´DYLE, _n._ Articular eminence of bone in hinge-joints.

CON´FLUENT, _a._ Run together; grown together; coalesced.

CONIROS´TRAL, _a._ Having a conical bill, like a sparrow’s.

CONJUNCTI´VA, _n._ Vascular membrane lining the eyelids and reflected over the front of the eyeball.

CON´NATE, _a._ Born or produced together; originally united; joined from the beginning. _Connation_ is earlier and more intimate or complete union than _confluence_.

CONTINU´ITY, _n._ Part of a thing between its ends in any way distinguished.

CON´TOUR FEATH´ERS, _n._ The general plumage of perfect feathers, lying external and determining the superficial shape of a bird. Distinguished from _down feathers_.

COR´ACOID (_bone_), _n._ Large stout bone connecting shoulder with sternum.

COR´DATE, COR´DIFORM, _a._ Heart-shaped.

CORIA´CEOUS, _a._ Denoting integument of dense, tough, leathery texture.

CO´RIUM, _n._ Same as CUTIS (which see).

COR´NEA, _n._ Transparent portion of the eyeball.

COR´NEOUS, _a._ Horny.

COR´NIPLUME, _a._ Tuft of feathers on head, erected like a horn.

COR´NU, _n._ Horn.

CORO´NA, _n._ Top of head. Equivalent to cap or pileus. Vertex is the highest point of corona.

COR´ONATE, _a._ Having coronal feathers lengthened or otherwise distinguished.

COR´PUS, _n._ Body, as a whole.

COR´PUS CALLO´SUM, _n._ Mass of transverse white fibres, connecting the cerebral hemispheres; wanting in birds.

COR´TICAL, _a._ External, as opposed to _medullary_.

COS´TAL, _a._ Pertaining to the ribs.

COSTIF´EROUS, _a._ Rib-bearing, as the dorsal vertebræ.

COT´YLE, _n._ Same as ACETABULUM.

COX´A, _n._ Hip.

CRA´NIAL, _a._ Pertaining to the skull.

CRA´NIUM, _n._ Skull.

CREST, CRIS´TA, _n._ Any lengthened feathers of top or sides of head.

CRIB´RIFORM, _a._ Sieve-like.

CRI´COID, _a._ Name of a certain laryngeal cartilage.

CRIS´SUM, _n._ Properly, the under tail-coverts collectively. Oftener used to designate the circumanal plumage. (66.)

CRO´TAPHYTE (_depression_). A concavity on the outside of the skull on each side behind, filled with muscle; temporal fossa.

CROWN, _n._ Pileus; top of head, especially the vertex.

CRU´CIAL, CRU´CIFORM, _a._ In the shape of a cross. The _crucial test_ is one experimentally conclusive.

CRURÆ´US, _n._ Name of a certain muscle of the thigh.

CRU´RAL, _a._ Pertaining to the crus, or shin.

CRUS, _n._ The shin; segment of the leg between the thigh and ankle, represented by the tibia.

CRYS´TALLINE (_lens_), _a._ See LENS.

CU´BIT, _n._ The forearm.

CU´BITAL, _a._ Pertaining to the forearm.

CU´CULLATE, _a._ Hooded.

CUL-DE-SAC, _n._ “Bottom of a bag”; closed end of a cavity.

CUL´MEN, _n._ Ridge of upper mandible; highest median lengthwise line of the bill. (20.)

CUL´MINAL, _a._ Pertaining to the culmen.

CULTRIROS´TRAL, _a._ Having the bill shaped like a heron’s.

CUN´EATE, CUN´EIFORM, _a._ Wedge-shaped. A cuneate tail has the middle feathers longest, the rest successively regularly shortened.

CUN´EIFORM (_bone_), _n._ One of the wrist-bones.

CURSO´RIAL, _a._ Running; pertaining or belonging to an obsolete group, _Cursores_ or runners.

CUS´PIDATE, _a._ Pointed as a spear-head.

CUTA´NEOUS, _a._ Pertaining to the skin. Same as _dermal_.

CU´TICLE, _n._ Scarf-skin; outermost layer of skin, which continually exfoliates.

CU´TIS, _n._ Skin; the true skin, as distinguished from cuticle and subcutaneous tissue. _Corium_ and _derma_ are synonymous.

CYST, _n._ Sac holding pathological products.

D.

DAC´TYL, _n._ Finger or toe. Equivalent to _digit_.

DACTYLOTHE´CA, _n._ Covering of the toes.

DASYPÆ´DIC, _a._ Synonymous with _ptilopædic_.

DECID´UOUS, _a._ Temporary; falling early. The dorsal plumes of the egret are _deciduous_.

DECOMPOSED´, _a._ Separate; standing apart. A _decomposed_ crest has the feathers standing away from each other.

DECUM´BENT, _a._ Lying or hanging downward.

DECURVED´, _a._ Gradually curved downward. Opposed to _recurved_.

DECUS´SATE, _a._ Crossed; intersected.

DEFECA´TION, _n._ Act of discharging the contents of the cloaca.

DEGLUTI´TION, _n._ Act of swallowing.

DEJEC´TION, _n._ Same as defecation. Also, the matters so discharged.

DEL´TOID, _a._ Triangular. A muscle over the shoulder is so named.

DEMI- (_in composition_). Half; same as _semi-_.

DEN´TARY, _a._ An epithet of the foremost element of the compound mandibular bone.

DEN´TATE, DENTIC´ULATE, _a._ Toothed; notched as if toothed.

DENTIG´EROUS, _a._ Bearing teeth. The _Ichthyornis_, _Apatornis_, and _Odontopteryx_ (?) are _dentigerous_ birds.

DENTIROS´TRAL, _a._ Having the bill notched as if toothed. Belonging to a certain obsolete order, _Dentirostres_.

DENTI´TION, _n._ Act of cutting teeth.

DENUDA´TION, _n._ State of nakedness; act of laying bare.

DENU´DED, _a._ Naked; laid bare.

DEOR´SUM. Below.

DEPLU´MATE, DEPLUMA´TUS, _a._ Bare of feathers. (4.)

DEPRESSED´, _a._ Flattened vertically. Opposite of _compressed_.

DERÆ´UM, _n._ Bottom or lower part of the neck. (Little used.)

DER´MAL, _a._ Pertaining to the skin; made of skin; cutaneous.

DER´MAL APPEN´DAGE. Any outgrowth from the skin.

DERTROTHE´CA, _a._ Covering of end of bill.

DER´TRUM, _n._ End of maxilla, in any way distinguished. (21.)

DESMOGNATH´OUS, _a._ Having the palate bones united.

DES´MOID, _a._ Ligamentous.

DESQUAMA´TION, _n._ Peeling off.

DEX´TRAD, _a._ Toward the right side.

DEX´TRAL, _a._ Of or on the right side.

DI- (_in composition_). Twice; double.

DIAGNO´SIS, _n._ Distinctive knowledge. Also characterization, or a brief, precise, and exclusively pertinent definition. _Diagnosis_ is nearly synonymous in this sense with _definition_; both differ from _description_ in omitting non-essential particulars; but _definition_ may include points equally applicable to some other object.

DIAGNOS´TIC, _a._ Distinctively and exclusively characteristic. Feathers are _diagnostic_ of birds.

DIAPH´ANOUS, _a._ Transparent.

DI´APHRAGM, _n._ Midriff; musculo-tendinous partition between thorax and abdomen, rudimentary or wanting in birds.

DIAPHRAGMAT´IC, _a._ Pertaining to the diaphragm.

DIAPOPH´YSIS, _n._ Transverse process of a vertebra.

DIARTHRO´SIS, _n._ Movable articulation of bones in general.

DIAS´TASIS, DIAS´TEMA, _n._ A separation of bones, particularly the cranial ones, or of teeth, from each other.

DIAS´TOLE, _n._ Dilatation of the heart, alternating with the _systole_ or contraction, occasioning pulsation.

DICHOT´OMOUS, _a._ Divided into pairs.

DICHROMATIC, _a._ Of two colors, as the “red” and “gray” plumages of _Scops asio_.

DIDAC´TYLOUS, _a._ Two-toed, as the ostrich.

DIGAS´TRIC, _a._ Double-bellied; name of a certain muscle.

DIGIT´IGRADE, _a._ Walking on the toes. Opposed to _plantigrade_.

DIGITUS, _n._; pl. _digiti_. Digit. Finger or toe. (116.)

DIMORPHIC, _a._ Of two forms.

DIPLO´Ë, _n._ Light spongy network of bone between inner and outer surface of the skull.

DISC or DISK, _n._ Set of radiating feathers of peculiar shape or texture around the eye of owls.

DISSEPIMEN´TUM NAR´IUM, _n._ Same as _septum narium_, which see.

DIS´TAD, _a._ Toward an extremity.

DIS´TAL, _a._ Remote; situate at or near an extremity; opposed to _proximal_.

DIS´TICHOUS, _a._ Two-rowed; spread apart on either side of a middle line, as the hairs of a squirrel’s tail, or the tail-feathers of the _Archæopteryx_.

DITOK´OUS, _a._ Producing but two eggs, as the pigeon and humming-bird.

DIUR´NAL, _a._ Pertaining to the daytime.

DIVAR´ICATE, _a._ Branching off; spreading apart; curving away.

DIVERTIC´ULUM, _n._ An offshoot of the small intestine.

DOR´SAD, _a._ Toward the back. Opposite of _ventrad_.

DOR´SAL, _a._ Pertaining to the back.

DOR´SUM, _n._ Back; upper surface of trunk from neck to rump. (57.)