344 ANATOMY OF THE DOMESTIC FOWL 



Make an incision through the skin down to the bone on the superior 

 part of the head, parallel and close to the base of the upper mandible, 

 and extending completely across. From the outer end of this make 

 an incision backward and down to the skull and posteriorly. The 

 muscles of the upper part of the neck will then be exposed. The 

 straight incision should extend to about a half inch on the inside of 

 the upper eyelid of the same side. Reflect the flap of skin from the 

 top of the skull, and carefully examine the under side of it in the 

 median line, where it overlies the frontal region. The dermo-fron- 

 talis will be observed if it be present. In many birds, especially in 

 females, it may not be discernible, and may be considered absent. 

 To expose the circumconcha^make an incision completely around 

 the ear; then carefully dissect to the ear base. A dermal circular 

 muscle should be observed. To expose the dermo-temporalis 

 extend the longitudinal incision down the back of the neck to a 

 point between the clavicular heads, carrying it just through the 

 skin and about one-fourth of an inch to the side of the median line. 

 Remove the skin from the throat and the anterior portion of the 

 chest. Lay open the alar and parapatagial duplicatures of the skin. 

 This exposes a number of dermal muscles. The dermo-temporalis 

 is now observed to extend from a small depression just above and 

 anterior to the temporal fossa. It makes slight attachments to the 

 temporal muscle, which it covers, and extends backward as a thin 

 ribbon-shaped muscle, the fibers blending with those of the cleido- 

 trachealis, and becomes lost upon trie skin in front and opposite the 

 shoulder-joint. At times its fibers blend with those of the dermo- 

 tensor patagii. 



As the musculature of the fowl is loosly arranged, the rest of the 

 dissection is easily done if care be exercised. 



The ligaments may be dissected after the completion of the study 

 of muscles, using the same subject or, a two pound broiler be pre- 

 pared by killing in the gas chamber, plucking the feathers and 

 parboiling just till the flesh becomes tender and is easily removed, 

 it will be observed that all structures can be removed from the 

 points exposing the ligaments distinctly. The ligaments appear 

 swollen and more easily observed for study. 



Directions for the Study of the Viscera. Carefully remove the 

 right and the left abdominal and thoracic walls, allowing a strip 

 of tissue to remain in the median line to hold the organs in their 

 normal position. To open these cavities it is necessary to use the 



