II.
EXPLANATION OF TERMS USED IN DESCRIBING THE EXTERNAL FORM OF BIRDS.
[Illustration: ½ NAT. SIZE.
_Turdus migratorius_, L.]
REFERENCES TO THE FIGURE.
N. B. In the figure the adjacent regions are separated by a double bar, with the letters belonging to each affixed.
A. The body in general. B. The region of the head. C. The region of the neck. D. The region of the trunk. E. The region of the tail. F. The region of the wings. G. The region of the legs. H. The feathers.
NOTE.—I am under obligations to Professor Sundevall of Stockholm and Dr. Sclater of London for assistance in correcting and improving the present article.—S. F. BAIRD.
B. Head.
9. Bill in general. 10. Maxilla. 11. Mandible. 20. Ridge. 21. Tip of maxilla. 22. Keel. 23. Angle of chin. 27. Angle of mouth. 28. Commissure. 28½. Nostrils. 30. Cap (pileus), includes 32, 33. 31. Crown (vertex). 32. Front head (sinciput). 33. Hind head (occiput). 34. Forehead. 36. Frontal points. 39. Lores. 40. Ophthalmic region. 41. Orbits. 42. Cheeks. 43. Eyebrows. 44. Temples. 45. Parotics. 46. Chin.
C. Neck.
48. Hind neck (includes 49, 50). 49. Nape. 50. Scruff. 51. Fore neck (includes 52, 53). 52. Throat. 53. Jugulum. 54. Side neck.
D. Trunk or Body.
57. Back (includes 58, 59). 58. Upper back. 59. Lower back. 60. Rump. 61. Mantle (back and wings together). 62. Breast. 63. Abdomen (includes 64, 65). 64. Epigastrium. 65. Belly. 66. Crissum.
E. Tail.
70. Tail feathers (or rectrices). 72. Upper tail coverts. 73. Lower tail coverts.
F. Wings.
75. Primary quills. 76. Secondary quills. 77. Bend of wing. 79. False wing (alula). 80. Scapulars. 86. Primary coverts. 89. Secondary coverts (include 92, 93, 94). 92. Greater wing coverts. 93. Lesser wing coverts. 94. Middle wing coverts. 95. Edge of wing.
G. Legs.
97. Thigh (concealed under skin). 98. Shin (tibia). 103. Heel joint. 103½. Tarsus. 112. Foot. 116. Toes. 126. Outer toe. 127. Inner toe. 128. Middle toe. 129. Hind toe.
For the purpose of defining the form, markings, coloration, and other peculiarities of birds, the different regions of the body have received names by which intelligible reference can be made to any portion. It is, perhaps, hardly necessary to say that all living birds have a head supported on a neck, with jaws extended into a bill covered with a horny sheath, or with skin, the two jaws situated one above the other, and always destitute of teeth. The anterior pair of limbs is developed into wings which, however, are not always capable of use in flight; the posterior serve as legs for the support of the body in an oblique or nearly erect position. The body is covered with feathers of variable structure and character, both in the young bird and the old. (The wings are apparently wanting in some fossil species.)
The following terms, English and Latin, are those most generally employed in describing the external form of birds, and are principally as defined by Illiger. In cases where there is no suitable English word in use, the Latin equivalent only is given. The figure selected for illustration, drawn by Mr. R. Ridgway, is that of the common American robin (_Turdus migratorius_, L.), and will be familiar to most students of ornithology.
A. Body in General (_Corpus_).
1. =Feathers= (_Plumæ_). A dry elastic object, with a central stem at one end forming a hollow horny tube implanted in the skin at its tip, the other feathered on opposite sides.
2. =Quills= (_Pennæ_). The large stiff feathers implanted in the posterior edge of the wing and in the tail.
3. =Plumage= (_Ptilosis_). The general feathery covering of the body.
4. =Unfeathered= (_Implumis_). A portion of skin in which no feathers are inserted.
5. =Upper parts= (_Notæum_). The entire upper surface of the animal. (Sometimes restricted to the trunk.)
6. =Lower parts= (_Gastræum_). The entire lower surface of the animal. (Sometimes restricted to the trunk.)
7. =Anterior portion= (_Stethiæum_). The forward part of the body (about half), both upper and under surfaces, including the chest.
8. =Posterior portion= (_Uræum_). The hinder portion of the body (about half), including the abdominal cavity.
B. The Head (_Caput_).
9. =Bill= (_Rostrum_). The projecting jaws, one above the other, united by a hinge joint behind, and covered by a horny sheath, or a skin, and enclosing the mouth.
10. =Maxilla=, or =upper jaw= (_Maxilla_).
11. =Mandible=, or =lower jaw= (_Mandibula_).
12. =Ramphotheca.= The horny covering, or sheath of the jaws.
13. =Rhinotheca.= The covering of the upper jaw.
14. =Gnathotheca.= The covering of the lower jaw.
15. =Cere= (_Cera_, or _Ceroma_). A skin at the base of the maxilla, in certain birds. (In birds without a horny sheath to the bill, the cere may be considered as extending to its very tip.)
16. =Edges of bill= (_Tomia_). The margins of upper and lower jaws where they come in contact. We have thus a
17. =Maxillary tomium=, and a
18. =Mandibular tomium.=
19. =Gape= or =Commissure= (_Commissura_). The junction of the tomia, or of the two bills.
20. =Ridge= (_Culmen_). The upper outline of the bill when viewed laterally; extending from base of bill to the
21. =Tip= (_Dertrum_).
22. =Keel= (_Gonys_). The lower outline of the bill viewed laterally; extending from the angle of the chin to the tip.
23. =Angle of the chin= (_Angulus mentalis_). The point where the two branches, or rami, of the lower jaw
24. (=Gnathidia=, _Rami_) unite, thence to be continued to its tip as the
25. =Myxa= (_Symphysis_).
26. =Malar region= (_Regio malaris_). The outside of the base of lower jaw; usually covered with feathers.
27. =Angle of the mouth= (_Angulus oris_). The angle formed by the mandible and maxilla; the posterior boundary of the gape or commissure, the tip of bill being the anterior.
28. =Nostrils= (_Nares_).
29. =Head=, as restricted (_Caput_). The head, exclusive of the bill.
30. =Cap= (_Pileus_). The whole top of head from the base of bill to nape.
31. =Crown= (_Vertex_). The highest central portion of the top of head (between the ears).
32. =Sinciput= (_Sinciput_). The anterior half of cap (from bill to middle of crown).
33. =Occiput= (_Occiput_). The posterior half of cap, (from middle of crown to the nape).
34. =Forehead= (_Frons_). From base of bill to crown (usually anterior to line of eye).
35. =Nape= (_Nucha_). See 49.
36. =Frontal points= (_Antiæ_). The two projecting feathered angles of the forehead embracing the base of the culmen, or included between the frontal angle of the maxilla and the angle of the mouth (not always present).
37. =Mastax= (_Mastax_). The side of the fore part of the head, adjacent to the base of the maxilla, and distinguished by its feathers or its color.
38. =Capister= (_Capistrum_). The anterior portion of the head all round the base of the bill.
39. =Lore= (_Lorum_). Narrow space between the bill and the eye, on each side.
40. =Ophthalmic region= (_Regio ophthalmica_). Space round the eye.
41. =Orbits= (_Orbita_). The innermost portion of the ophthalmic region immediately adjacent to the eye.
42. =Cheeks= (_Genæ_). See Malar region.
43. =Eyebrow= (_Supercilia_). A longitudinal stripe immediately above the eye.
44. =Temples= (_Tempora_). Whole side of the head behind the eye or between the eye, top of head, and the ear.
45. =Parotic region= (_Regio parotica_). Space around the ears.
46. =Chin= (_Mentum_). Space embraced between the branches of lower jaw.
C. The Neck (_Collum_).
47. =Neck= (_Collum_). The part connecting the head and trunk, enclosing the neck vertebræ.
48. =Hind-neck= (_Cervix_). The upper or posterior portion of the neck, from occiput to back.
49. =Nape= (_Nucha_). The portion of hind neck nearest the head.
50. =Auchenium= (_Auchenium_). The portion of hind neck nearest the back, the “scruff” of the neck.
51. =Fore-neck= (_Guttur_). The inferior or anterior portion of neck, from the chin to the breast.
52. =Throat= (_Gula_). The upper part of fore neck, or that nearest the chin.
53. =Jugulum= (_Jugulum_). The lower part of fore neck, between the throat and the breast. (Divided into upper, middle, and lower.)
54. =Side neck= (_Parauchenium_). The sides of the neck, between the front and the hind neck.
55. =Collar= (_Torques_). A ring of any kind encircling the neck.
D. The Trunk (_Truncus_).
56. =Trunk= (_Truncus_). That portion of the body enclosing the viscera and intestines, and carrying the neck and head at one end, the tail at the other, as also the four limbs.
57. =Back= (_Dorsum_). The portion of the upper surface of the trunk, from the neck to the rump, and corresponding to the dorsal and sacral vertebræ.
58. =Upper back= (_Interscapulium_). The upper portion of the back, or along the dorsal vertebræ; between the shoulder-blades, and opposite the breast, sometimes called _dorsum anticum_.
59. =Lower back= (_Tergum_). The lower portion of the back along the saeral region, from the upper back to the rump, and opposite the belly, sometimes called _dorsum posticum_.
60. =Rump= (_Uropygium_). The portion of the upper side of the trunk corresponding to the caudal vertebræ.
61. =Mantle= (_Stragulum_; _Pallium_). The back and the outside of the folded wings taken together.
61½. =Ventral region= (_Regio ventralis_). Under side of body, including breast and abdomen.
62. =Breast= (_Pectus_). The most anterior portion of the lower surface of trunk, representing the region of the sternum or breast bone (between the jugulum and the abdomen).
63. =Abdomen= (_Abdomen_). The under side of body, between the breast and the anal region.
64. =Epigaster= (_Epigastrium_). The anterior portion of abdomen, next to the breast.
65. =Belly= (_Venter_). The hinder portion of the abdomen, next to the anal region or crissum.
66. =Anal region= (_Crissum_). The region around the anus, below the tail, and opposite to the rump. Frequently includes under tail coverts.
67. =Flanks= (_Hypochondria_). The sides of the soft parts of the body.
68. =Humeral region= (_Regio humeralis_). The anterior portion of the sides; that in which the wing is implanted.
E. The Tail (_Cauda_).
69. =Tail= (_Cauda_). The feathers forming the posterior extremity of the body, implanted on the os coccygis, or rump bone.
70. =Tail feathers= (_Rectrices_). The long individual feathers belonging to the tail.
71. =Tail coverts= (_Calypteria_). The feathers overlying and covering the base of the tail feathers; the
72. =Upper= (_superiores_) being those above, and
73. =Lower= (_inferiores_) those below; sometimes concealing or projecting beyond the tail.
NOTE.—_Tegmina_ (73½) are coverts in general, whether of wing or tail. _Calypteria_ are tail coverts. _Tectrices_ (83), wing coverts.
F. The Wings (_Alæ_).
74. =Wings= (_Alæ_). The anterior pair of limbs of the bird, used in flight.
75. =Primary quills=, or =quills of the first series=; =Hand-quills= (_Remiges primariæ_). The (usually) ten stiff feathers inserted on the hand or first joint (metacarpus and digit), or from the bend of the wing to the tip.
76. =Secondary quills= or =quills of the second series=; =Arm-quills= (_Remiges secundarii_; _Pennæ cubili_). The inner quills, or those inserted along the posterior edge of the forearm or cubitus. The innermost of these quills, sometimes longer or different from the rest, are frequently called tertials. (_Pennæ tertiariæ._)
77. =Bend of the wing= (_Flexura_, _Plica_). The angle of junction of the hand-joint and that of the forearm.
78. =Armpit= (_Axilla_). The under side of the insertion of the wing into the body.
79. =False= or =Bastard wing= (_Alula_). A series of several stiffened feathers on the edge of the wing, overlying and exterior to the primary quills, and inserted on the thumb joint of the hand.
80. =Scapulars= (_Pennæ scapulares_). Stiffened feathers inserted on the shoulder-blade or the insertion of arm (_humerus_), and filling up the interval between the secondary quills and the body.
81. =Axillars= (_Pennæ axillares_). Similar feathers connecting the under surface of the wing and the body, and concealed in the closed wing.
82. =Speculum=, or =Mirror= (_Speculum alæ_). A brilliantly colored portion of the wing especially in the ducks, over the extremities of the secondary quills, and framed in on one side (in the closed wing) by the primary quills, or the other by the scapulars.
83. =Wing coverts= (_Tectrices_). The smaller feathers of the wing. The
84. =Upper= (_superiores_), side above or outer. The
85. =Lower= (_inferiores_), below, or inside, and overlying the bases of the quills. These and the quills form the surfaces of the wings.
86. _Primary coverts_ (_Tectrices primariæ_). The feathers, which either
87. =Upper= or
88. =Under= overlie the bases of the primary quills. These are on the upper or under surface of the wing; not often distinguished in descriptions.
89. =Secondary coverts= (_Tectrices secundariæ_). The feathers which, as
90. =Upper= and
91. =Under=, cover the bases of the secondary quills, on the upper or under surface of the wings, being generally those referred to as “coverts.”
92. =Greater coverts= (_Tectrices majores_). The longest coverts projecting beyond the rest, and resting directly upon the bases of the secondary quills.
93. =Lesser coverts= (_Tectrices minores_). The succession of many series of small feathers beginning at and covering the anterior edge of the wing, very small at first and increasing in size behind.
94. =Middle coverts= (_Tectrices mediæ_). One or more rows of coverts, intermediate in size as well as position, between the lesser and greater coverts.
95. =Edge of the wing= (_Campterium_; _Margo carpi_). The small feathers covering the anterior edge of the wing, both along the forearm and the hand or first joint, including the bend of the wing.
G. The Legs (_Pedes_).
96. =Legs= (_Pedes_). The posterior pair of limbs inserted in the pelvis, and used in walking or running.
97. =Thigh= (_Femur_). The basal joint of the leg, its head articulating with the pelvis. This is generally imbedded in the flesh, and covered by the skin so as not to be appreciable, especially in the prepared specimen.
98. =Shin= (_Tibia_). The second or middle joint of the leg, articulated above to the thigh, below to the tarsus. The upper part, sometimes the whole, is enveloped in flesh, and covered by skin and feathers; sometimes the lower extremity is covered by horny plates, the
99. (=Cnemidium=).
100. =Foot joint= (_Podarthrum_). The junction of the tarsus below with the foot.
101. =Podotheca= (_Podotheca_). The horny or skinny covering of lower tibia, tarsus, and feet.
102. =Knee= (_Genu_). The junction of the thigh with the leg, usually concealed by the skin.
103. =Heel joint= (_Suffrago_). The junction of the leg with the tarsus.
103½. =Tarsus= (_Tarsus_). The third joint of the leg and next to the tibia; covered generally with horn, sometimes with naked skin or feathers, never with flesh; the toes are articulated to its lower extremity. This joint corresponds to the ankle joint of the human body.
104. =Instep=, or =Front of tarsus= (_Acrotarsium_). The anterior face of the tarsus, usually covered by small plates, which in the higher groups are united into one; sometimes covered by skin.
105. =Side of tarsus= (_Paratarsium_).
106. =Back of tarsus= (_Planta tarsi_). Homologically the =Sole= (_Planta_).
107. =Heel= (_Calcaneus_; _Talus_). The upper posterior extremity of the tarsus.
108. =Spur= (_Calcar_). Any bony sharp process or spine implanted on the tarsus, as in the rooster.
109. =Scutellæ= (_Scutella_). The succession of small, usually rectangular plates, applied against the anterior face of the tarsus, and the upper surface of toes. These sometimes encircle the tarsus completely, meeting on the inner side; sometimes reach half round with similar half-rings on the back side of the tarsus; are sometimes divided into polygonal plates; are sometimes fused into a continuous plate, either anteriorly or laterally. Modifications of structure in this respect indicate differences in rank and systematic position of the highest value.
110. =Scutellate tarsus.= When the tarsus is covered with transverse or polygonal scales, as described above.
111. =Booted tarsus.= Where the anterior face is covered with a continuous horny plate not divided into scutellæ.
112. =Foot= (_Pes_). The toes and tarsus taken together.
113. =Top of foot= (_Acropodium_). The entire upper surface of the foot.
114. =The track= (_Pelma_). The entire lower surface of the foot.
115. =Heel pad= (_Pterna_; _Tuber_). The posterior portion of the _pelma_, immediately under the joint of the foot, and frequently prominent.
116. =Toes= (_Digiti_). The, usually four, sometimes three, very rarely two, articulated portions of the leg hinged on the lower extremity of the tarsus. When all four are present, one is usually behind, sometimes two before, and two behind.
117. =Top of toes= (_Acrodactylum_). The upper surface of the toes individually.
118. =Soles of toes= (_Hypodactylum_). The lower or plantar surface of the toes individually.
119. =Side of toes= (_Paradactylum_). The sides, in any way distinguished from the soles.
120. =Phalanges.= The several bones composing a toe.
121. =Claw= (_Ungues_). The horny tips sheathing the last joint of the toes.
122. =Claw joint= (_Rhizonychium_). The terminal bone of the toe, carrying or armed with the claws.
123. =Pads= (_Tylari_). The swellings or bulbs on the under side of the phalanges. Those =Toes= are
124. =Anterior= which are directed forwards;
125. =Posterior=, directed backwards;
126. =Exterior=, on the outer side of the foot;
127. =Interior=, on the inner side of the foot; the
128. =Middle toe= is the central of three toes directed forwards.
129. =Hind toe= (_Hallux_). The single toe directed backwards. This is homologically the first or great toe directed backward. It is
130. =Insistent= (_insistens_), when the tip at least touches the ground, but the base raised above the level of the rest;
131. =Incumbent= (_incumbens_), when its whole under surface touches the ground; and
132. =Elevated= (_elevatus_; _amotus_), when raised so high that the tip does not touch the ground at all.
133. =Unarmed toe= (_Digitus muticus_). Toe without a claw. The tarsus is unarmed when without a spur.
134. =Fringed toe= (_Digitus lomatinus_). A lateral membranous margin to the toes. This
135. =Fringe= (_Loma_) may be
136. =Continuous= (_continuum_), or
137. =Lobed= or =Scolloped= (_lobatum_).
138. =Membrane= (_Palama_). A skin either soft or covered with scales or feathers connecting two adjacent toes together at the base, and sometimes extending to or beyond their tips. The foot so constructed is called
139. =Palmate= (_palmatus_) when the anterior toes only are so connected and
141. =Oared= (_Steganopus_), where all the toes, including the hinder, are so connected in the cormorants, etc. The feet may be half, or semipalmate; entirely or totipalmate.
NOTE. In the usual arrangement of the toes, of three before and one behind, the hinder corresponds to the great toe of man, or the first; the inner anterior is the second; the middle is the third; and the outer is the fourth. When the toes are in pairs or two before and two behind, it is the outer or fourth toe that is turned backwards, as is the woodpeckers. In the Trogons, however, the inner toe is reversed. With scarcely an exception in birds, the hinder or first toe has two joints; the inner (2d) has three; the middle (3d) has four; and the outer (4th) has five, or a formula of 2.3.4.5. In the typical _Caprimulgidæ_ the outer toe has only four phalanges the formula being 2.3.4.4. Finally, in some _Cypselidæ_ (_Cypselus_ and _Panytila_), we have the middle and outer toes with three joints only each, the formula being 2.3.3.3. When there are but three toes, the hinder or first is wanting; the ostrich (_Struthio_) has but two toes, lacking the first and second.
H. The Outer Covering (_Indumentum_).
142. =Outer covering= (_Indumentum_; _Ptilosis_). The exterior of the bird in detail.
143. =Feathers= (_Plumæ_). Composed of the _stem_ and the _webs_.
144. =Stem= (_Scapus_). The entire central axis of the feather.
145. =Quill= (_Calamus_). The hollow horny basal portion of the feather.
146. =Shaft= (_Rhachis_). The solid terminal portion of the stem in which the fibres are implanted.
147. =Webs= (_Pogonia_). The series of fibres implanted on each side the shaft, generally stiff, and having little
148. =Hooks= or =barbules= along the edges, by which adjacent ones interlock; sometimes soft, with the barbules not interlocking, the barbules sometimes wanting. The
149. =Inner web= (_Pogonium internum_) is situated on the inner side of the shaft; the
150. =Outer= (_externum_), on the outer side.
151. =Vane= (_Vexillum_). The shaft and webs taken together, or the portion of the feather left when the barrel or quill is cut away.
GLOSSARY.
GLOSSARY OF TECHNICAL TERMS USED IN DESCRIPTIVE ORNITHOLOGY.
_Including a number of prominent Anatomical and Physiological Terms._
(PREPARED BY DR. COUES.)
NOTE.—The number in parenthesis refers to the foregoing “Explanation of Terms,” etc. The sign (´) marks accent; _n._, noun; _a._, adjective; _pl._, plural; _gen._, genitive.
A.
ABDO´MEN or AB´DOMEN, _n._ Belly; part of gastræum between sternum and anus. (63.)
ABDOM´INAL, _a._ Pertaining to the belly.
ABDUC´TION, _n._ Act of carrying a limb away from the axis of the body. Opposed to _adduction_. Muscles so acting are _abductors_.
ABER´RANT, _a._ Deviating from ordinary character.
ABNOR´MAL, _a._ Of highly unusual, extraordinary character; deformed; monstrous.
ABOR´TIVE, _a._ Suppressed; remaining or becoming imperfect. The nostrils of the cormorant are _abortive_.
ACAR´IDES, _n. pl._ Certain external parasites.
ACCIP´ITRINE, _a._ Hawk-like; belonging to _Accipitres_.
ACCLIMATIZA´TION, _n._ Naturalization, with reference to the effect of a new country upon the economy.
ACETAB´ULUM, _n._ Pelvic cavity for reception of head of femur.
ACHIL´LIS (_tendo_), _n._ Tendon of principal extensor muscle of foot.
ACIC´ULAR, _a._ Needle-shaped; sharp and very slender.
ACRODAC´TYLUM, _n._ Top of toes collectively. (117.) (Little used.)
ACRO´MION, _n._ Process of the scapula.
ACROPO´DIUM, _n._ Entire upper surface of foot. (113.) (Little used.)
ACROTAR´SIUM, _n._ Front of tarsus, corresponding to the human instep. (104.) (Little used).
ACU´MINATE, _a._ Tapering gradually to a point.
ACUTE´, _a._ Sharp-pointed.
AD- (_in composition_). To; towards.
ADDUC´TION, _n._ Act of drawing a limb toward axis of body. Muscles so
## acting are _adductors_. Compare ABDUCTION.
AD´ENOID, _a._ Glandular; glandiform.
AD´IPOSE (_tissue_), _a._ for _n._ Cellular tissue holding fat in special vesicles.
ADOLES´CENCE, _n._ Youth.
ADRE´NAL (_body_), _a._ for _n._ A small organ capping the kidney.
ADULT´, _a._ or _n._ Grown to full size; mature.
ÆGITHOGNATH´OUS, _a._ Having the palate bones disposed as in a sparrow or other passerine bird.
AF´FERENT, _a._ Bringing to or towards. Opposed to _efferent_.
AFFINED´, _a._ Joined or related by affinity.
AFFIN´ITY, _n._ Quality of direct relation; conformity; agreement. Morphological _affinity_ implies relationship by genetic descent; teleological _affinity_ cannot be properly predicated.
AF´TER-SHAFT, _n._ Scape or stem of the supplementary plume springing from many feathers, or, oftener, such plume itself.
AL´A, _n._; pl. _alæ._ Wing; the anterior limb of birds. (73.)
A´LAR, _a._ Pertaining to the wings.
ALAT´US, _a._ Winged.
AL´BINISM, _n._ State of whiteness, complete or partial, resulting from deficiency or entire lack of pigment in the skin and its appendages.
ALBI´NO, _n._ An animal affected with albinism.
ALBINOT´IC, _a._ Affected with albinism.
ALBU´MEN, _n._ Transparent glairy fluid of which white of egg mainly consists.
ALBU´MINOUS, _a._ Containing or consisting of albumen.
ALIMEN´TARY, _a._ Pertaining to the digestive organs or nutritive function.
ALISPHE´NOID, _n._ “Wing,” or expanded part of sphenoid bone.
ALLANTO´IS, _n._ A certain organ of the embryo.
AL´LEX, _n._ Same as HALLUX (which see).
AL´TRICES, _n. pl._ Birds reared in the nest and fed by the parents.
ALTRIC´IAL, _a._ Having the nature of _Altrices_.
AL´ULA, _n._ Literally, little wing. The bastard wing, composed of the feathers that are set on the so-called thumb.
AL´ULAR, _a._ Pertaining to the bastard wing.
ALVE´OLUS, _n._ Socket, particularly of a tooth.
AL´VINE, _a._ Pertaining to the lower belly (said chiefly of intestinal discharges).
AM´BULATORY, _a._ Same as GRADIENT (which see).
AM´NION, _n._ A certain organ of the embryo.
AMO´TUS, _a._ Denoting the hind toe so elevated and short that the tip does not touch the ground. (132.)
AMPHIARTHRO´DIAL, _a._ Denoting a sliding joint, or one capable of mixed movement.
AMPHICŒL´IAN, _a._ Said of a vertebra when both ends of its centrum are cupped. Corresponding terms are _procœlian_, cupped in front, and _opisthocœlian_, cupped behind.
AMPUL´LA, _n._ A certain cavity of the inner ear.
A´NAL, _a._ Pertaining to the anus; situated about the anus.
ANALOG´ICAL, _a._ Having analogy; related by analogy.
ANAL´OGY, _n._ Quality of likeness in certain (generally superficial or inconsiderable) respects, between things essentially unlike. There may be analogy entirely without homology, as between the wing of a bird and of a butterfly.
ANASTOMO´SIS, _n._ Inosculation or intercommunication of two or more vessels.
AN´ATINE, _a._ Duck-like.
ANCHYLO´SIS or ANKYLO´SIS, _n._ Restriction or loss of motion in a naturally movable joint; also, any coössification.
AN´CONAL, _a._ Pertaining to the elbow.
ANGLE OF CHIN = ANGULUS MENTI. (23.)
ANGLE OF MOUTH = ANGULUS ORIS. (27.)
AN´GULUS O´RIS, _n._ Corner of the mouth; equivalent to commissural point.
AN´NOTINE, _n._ A bird one year old, or which has once moulted.
AN´NULAR, _a._ Ringed.
AN´NULUS, _n._ Ring.
ANOM´ALOUS, _a._ Extremely irregular; very strange or unusual; contrary to natural order (nearly synonymous with _abnormal_).
AN´SERINE, _a._ Pertaining to the _Anseres_; goose-like.
AN´TE- (_in composition_). Before; as, _anteocular_, _anteorbital_, etc.
ANTERIOR, _a._ Forward; in front of.
ANTERIOR PORTION. (7.) See STETHIÆUM.
ANTERIOR TOES. (124.)
AN´TI- (_in composition_). Against.
AN´TIÆ, _n. pl._ Frontal points; projections of feathers on either side of base of culmen. (36.)
ANTIBRACH´IUM, _n._ Cubit or forearm.
A´NUS, _n._ Outlet of refuse of digestion. In birds, the same orifice discharges the products of the genito-urinary organs.
AOR´TA, _n._ The first great artery, immediately issuing from the left ventricle of the heart.
AOR´TIC, _a._ Pertaining to the aorta.
APERTU´RA, _n._ An opening; as, _apertura auris_, ear-opening.
A´PEX, _n._; pl. _apices_. Tip or point of anything.
APOHY´AL, _a._ A portion of the “horn” of the hyoid bone.
APONEURO´SIS, _n._ Broad, strong, fibrous membrane or band; fascia.
APOPH´YSIS, _n._ Any natural bony prominence of notable size.
APPOSED´, _a._ Mutually fitted, adapted; set over against; meeting closely and exactly. The tomia of the bill are usually _apposed_.
APTE´RIUM, _n._; pl. _apteria_. Tract of skin where no feathers grow. Compare PTERYLA.
AQUAT´IC, _a._ Pertaining to the water; said of birds frequenting water, and thence drawing subsistence.
A´QUEOUS, _a._ Watery. Said of the fluid in the anterior chamber of the eye. See VITREOUS.
AQ´UILINE, _a._ Eagle-like; belonging to the _Aquilinæ_.
ARACH´NOID, _n._ One of the three enveloping membranes of the brain, between the _dura mater_ and the _pia mater_.
ARBOR´ICOLE, _a._ Tree-inhabiting.
ARCH´ETYPE, _n._ Original plan or idea of structure, modified or lost by subsequent specialization.
ARCHETYP´ICAL, _a._ Having the primitive pattern or original plan of structure.
ARC´UATE, _a._ Bow-shaped; bent regularly and gradually.
ARE´OLA, _n._; pl. _areolæ_. Small naked space on the feet between scales.
ARE´OLAR TISSUE. The light cellular connective tissue of the body.
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.