A History of North American Birds; Land Birds; Vol. 3 of 3

by Spencer Fullerton Baird; T. M. Brewer; Robert Ridgway

• 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).