UPPER HALF OF RABBIT. 17 



5. UPPER HALF OF RABBIT (Lepus cunicuhis), 



Dissected so as to show some of the muscles of the head, neck, shoulder, and fore-leg '. The letters 

 and the description correspond with those on the figure annexed. 



With Figure I . 



THE skin has been removed from the front of the lower jaw backwards, 

 the sheet of cutaneous muscle, x, covering the region of the neck and 

 known in anthropotomy as the panniculus carnosus or platysma myoides, has 

 been entirely removed on the right side, as also from the region of the 

 thorax on both sides ; the incomplete clavicle with the muscles in con- 

 nection with it has been separated from its ligamentous union with the 

 sternum and displaced to the right so as to show the subjacent nerves, 

 phrenic and brachial, on the same side ; below the level of the clavicle, 

 portions of the pectoral, c, d, and the sterno-clavictdar muscles, g, have 

 been dissected and turned back. On the left side, the anterior part of the 

 panniculus carnosus has been left with its two fixed insertions,^ and x\ into 

 the lower jaw, and the other, x"', into the sternum, intact ; the clavicle is 

 left in situ, but the muscles passing down to it from the head have been cut 

 away behind the line of the cutaneous muscle to show the sterno-scapular 

 muscles, h and z, in connection with the clavicle, at j ; and the serratus 

 magnus, o. The deep cervical fascia (/3) is seen to the left of the middle 

 line of the upper half of the neck and of the intermandibular space, at a 

 lower level than the panniculus carnosus. It has been removed anteriorly 

 to show the insertion of the digastric muscle. On a level with the hyoid 

 the deep cervical fascia is raised into a convexity (a') by the submaxillary 

 gland underlying it, and it furnishes, externally and posteriorly to this area, 

 a capsule to the parotid. This gland, however, being less convex than the 

 submaxillary, does not cause the sheet of fascia to bulge upwards. On the 

 opposite side this fascia has been removed in the intermandibular space ; 

 and the submaxillary gland being raised from its bed is seen to send a duct 

 in towards the mouth in an interspace between the internal pterygoid and 

 digastric muscles. This latter muscle is in the Rabbit, as in many other 

 mammals, monogastric, its posterior belly being represented by a tendon, 

 which however pierces the stylo-hyoid just as in man. Its muscular portion 

 is inserted into the lower jaw on either side of the symphysis, and from the 

 same portion of the jaw a depressor , w, of the lip passes forward. On the 



1 It is for various reasons advisable that the student should proceed to the preparations illustrating 

 the splanchnology of the Rabbit before addressing himself to this somewhat complex dissection. 

 And it will be found advantageous to immerse the upper half of the body of the animal, the heart 

 and lungs having been removed, in spirit 10 over proof (sp. gr. 910) for three or four days before 

 following out the detailed anatomy of the muscles here described and figured. For making special 

 dissections of the nerves it will be found useful to acidulate the spirit with dilute nitric acid in the 

 proportion of one part in forty. This treatment facilitates the mechanical process of dissection 

 in several ways, and makes it less easy to overlook the more delicate structures concerned. 



C 



