OF THE WOMBAT, KOALA, AND PHALANGERS. 



867 



last is absent \i\ Phascolarctos and Phascolomys. The insertion of 

 stevno-mastoid and cleido-mastoid is into the occipital crest. 



Genio-hyoicl : — In mj specimen of Phascolarctos it I'unsfrom the 

 symphysis of the mandible to the hyoid bone and thyroid carti- 

 lage, so it is in reality a genio-hyo-thyroid. This arrangement 



Text-figure 33. 



Anatomy of the neck in Fhalanger orientalis (adult). 



CL-0 : cleido-occipital ; Pect.Maj : pectoralis major; T.G : thyroid gland. Other 

 letters as iu last figure. In a mammary fcetus the cervical thymus concealed 

 the lower part of the neck. Nota the vertical anterior jugular veins and the 

 horizontal vena transversa. 



dijEfers from Young's account (14). As no other thyro- hyoid 

 muscles are present, they are probably replaced by a part of the 

 genio-hyoid. 



The genio-hyoids and stylo-hyoids are the only muscles 



