Part 124

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.