152 



HITCHCOCK'S ANATOMY 



282. Suspensory Muscle —In the turkey and birds of like 

 character an especial muscle is provided for the support of 

 the crop, which so often becomes heavily loaded with food. 



283. Muscles of Birds' Feathers — Their Use— Their 

 Number — Muscles of the Breast. — Birds are supplied with 

 tegumentary muscles somewhat after the manner of quadru- 

 peds. The main difference is, that in birds a few muscular 

 fibers are sent to each quill feather of the body, by which the 

 feathers can be violently shaken to dislodge dirt, or they may 

 be merely raised on end by the same muscles. This property 

 is well seen in common barn fowls, when they shake them- 

 selves after having lain in dry dirt. A hen with a brood of 

 chickens, too, when disturbed shows her wish to protect her 

 young by ruffling up her feathers and attacking whoever may 

 annoy her. In some birds, where there are 3,000 quill feath- 

 ers, the number of muscles must be at least 12,000. No 

 muscles are found upon the face of birds, but to secure the 

 degree of motion to which the head is subject, and the flexi- 

 bility of the neck, the muscles of this portion of the body are 

 very strongly developed. The most powerful muscles of 

 birds are the pectoral, or those on the breast ; one end of 

 which is attached to the keel of the sternum and the other to 

 the humerus. These muscles are three in number on each 

 side, and the largest one exceeds in weight all the other mus- 

 cles of the body. 



284. Muscles of Fishes —The muscles of fishes are char- 

 acterized by their slight degree of separation from one an- 

 other, by the absence of long tendons, and the softness of their 

 fibers. Their color is generally white, or yellowish white, 

 but in microscopic structure they do not differ from those of 

 the other vertebrata. By far the largest part of the fleshy 



2S2. What peculiar muscle is found in birds like the turkey ? 283. What is worthy of 

 note in the tegumentary muscle of birds? In Avhat condition does a hen show the ac- 

 tion of the tegumentary muscles ? What number are there in some birds? Why is 

 there need of so lew muscles on the head of birds? Upon what portion of the body are 

 there the most muscles? Give the actual amount by weight. 284. What is the peculiar 

 feature of the muscle of fishes ? Give their color. 



