66 



MK. F. G. PARSONS OJST THE 



is specially well developed. The achselbogen passing from the 

 c'orso-bumeralis across the axilla are well marked. Deep to the 

 platysma is a very definite sphincter colli, which, however, does 

 not reach back so far as the sternum. The facial muscles are 

 simple, and consist of a retractor naris rising below and in front 

 of the orbit and dividing into several fine tendons, orbicularis 

 oris and palpebrarum, frontalis, depressor labii inferiorie, four 

 anterior auricular muscles and two posterior. The most curious 

 of the facial muscles is one which I have never met with 

 in other mammals : it rises from the root of the zygoma and 



Fig. 2. 



1. Temporal. 2. Buccinator. 3. Eetractor naris. 4. Deep Parotido-auri- 

 cularis. 5. Superficial Masseter. 6. Deep Masseter. 7. Third part of 

 Masseter. 8. Auditory Meatus. 



passes ixpward and backward, deep to the parotid, to be inserted 

 into the commencement of the helix. I would suggest the name 

 of deep parotido-auricularis for it. There is no distinct zygo- 

 maticus or levator labii superioris. 



Muscles of Mastication. 



The Temporal does not meet its fellow in the mid-line of the 

 skull, it is divided into two very distinct planes. 



The Masseter also has- the two planes very clearly separated : 

 the superficial rises by a narrow tendon from the malar, and 

 spreads out in a fan-like way to be inserted into the lower margin 

 of the mandible as far back as the tip of the angular process : 

 the deep plane is also fan-shaped, but is inverted, the broad part 

 rising from the whole length of the zygoma, while the insertion 

 converges to the outer surface of the ramus of the jaw. 



A third slip of the masseter w^hich I have never found 

 in other mammals rises from the cartilage of the external 



