OF THE WOMBAT, KOALA, AND PHALANGERS. 893 



B: Characters separating Phascoloonys from Phascolarctos and 

 the Phalangeridse : — 



1. Formation of the alisphenoid bulla. 



2. Site of occipital processes. 



3. Pieces in sternum. 



4. Third trochanter of femur. 



5. Dentition. 



6. Some of the characters of manus and pes. 



C. Characters in which Phascolarctos differs from the Phalangers 

 and Phascolomys. 



External Characters : — Pocock (9) showed that there is a 

 rhinarium in Phascolomys and the Phalangeridse, but no true 

 rhinarium is present in Phascolarctos ; and the nostrils of the 

 latter are also peculiar. In the same paper he deals with the 

 characters of the marsupium, and points out that Phascolomys is 

 intermediate between the Phalangeridie and Phascolarctos. More- 

 over, the pouch of the latter is not closely related to that of any 

 genus of the Phalangeridse. 



Myology : — In the summary of myological features at the end 

 of the first part of this paper I enumei-ated many conditions 

 representing adherence to the primitive lamination of the muscles. 

 But these cannot be used for purposes of classification. 



The other points ai^e given in the following table : — 



JPhascolarcfos. 



1. Occipital crest curves backwards. 



2. Alisphenoid bulls as long as ex- 



occipital processes. 



3. Characters of nasal bones. 



4. Anterior margin of septum nasi con- 



cave. 



5. First dorsal spine scarcely exceeds 



seventh cervical. 



6. No patella. 



7. Vagina musculina present. 



8. No azygos lobe. 



9. Epiglottis entire and far from tongue. 



10. No faucial tonsil. I 10. Faucial tonsils present 



11. Thick ureteric venous plexus. I 11. Absent. 



Phascolomys and Phalangeridse. 



1. Not so. 



2. Not so in Phalangers. Bulla 

 temporal in Fhascolomys. 



4. Convex. 



6. Patella thin and cartilaginous. 



7. Absent. 



8. Right lung has azygos lobe. 



9. Epiglottis notched and close to tongue. 



D. Characters differing in all forms. 



In the first part of this paper I described no fewer than thirty- 

 two myological features differing in all forms. But these fall 

 into primitive and adaptive groups, and are useless for purposes 

 of classification. As regards visceral anatomy, there are many 

 points difTering in all forms. Some of these are undoubtedly 



