MYOLOGY or AJSTOMALTJEUS. 



333; 



Comparison of Muscles of Anomalurus and Pedetes. 



In these 17 points there are 12 in which the arrangement is 

 the same in both animals, but it must be remembered that many 

 of these simply denote myomorphine tendencies on the part of 

 botb ; and in the five points in which they differ (Nos. 1, 3, 10, 

 14, and 17) the divergence is always towards the Hystricomorpha 

 on the part of Pedetes, and the Sciuromorpha on the part of 

 Anomalurus. 



There are, however, three points (Nos. 4, 7, and perhaps 15) in 

 which, both animals wander away in the same direction from the 

 arrangement which one might have predicted for them : it may 

 be wortb while considering these points in detail. 



The first is the case of the omo-hyoid, which is absent in both 

 animals, although it is constantly present in the Sciuromorpha 

 and Myomorpha. In the Hystricomorpha it is present or 

 absent, and its absence in Pedetes does not surprise us when the 

 many hystricomorphine affinities of that animal are remembered. 

 Its absence in Anomalurus is unexpected, and may be the 

 residt of an individual variation in the animal I dissected, or 



lilNN. JOUEN. — ZOOLOGY, YOL. XXVII. 25 



