MYOLOGY OF ANOMALUEUS. 329 



10. The presemimembranosus is quite distinct from tlie 



adductor mass. 



11. The gracilis is usually double. 



12. The flexor tibialis does not usually join the flexor fibularis 



in the sole. 



13. The accessorius is absent. 



14. The rhomboideus capitis is usually distinct from the rest 



of the rhomboid sheet. 



15. The rectus ventralis often decussates with its fellow at its 



origin. 



Anomalurus agrees with the Myomorpha in the following 

 characters — ISTos. 1, 2, 3, 5, 6, 8, 9, 12. But it must be borne in 

 mind that Nos. 2, 3, 5,6, 8, and 12 are points which are common 

 to both Sciuromorpha and Myomorpha. 



From a comparison of the foregoing, it will be seen that in the 

 greater number of characteristic muscles Anomalurus agrees with 

 both the Myomorpha and Sciuromorpha, but that, where these 

 muscles vary in the two suborders, it agrees with the Sciuro- 

 morpha in six and with the Myomorpha in two. 



The six points which mark its sciuromorphine affinities are : — 



1. The presence of all three parts of the coraco-brachialis. 



2. The close connection of the presemimembranosus with the 



adductor mass. 



3. The single gracilis. 



4. The presence of the accessorius pedis. 



5. The rhomboids forming one sheet. 



6. The non-decussation of the rectus ventralis. 



Of these I regard Nos. 1, 2, 3, and 4 as of great importance. 



The two points of myomorphine affinity are : — 



1. The passage of a small part of the masseter through the 



infraorbital foramen. 



2. The absence of the supinator longus. 



The second of these is a negative point, and probably too much 

 stress should not be laid upon it ; but the first is a point 

 of great importance and to my mind shows undoubted myo- 

 morphine tendencies. 



With regard to the Hystricomorpha there is no need to go into 

 so much detail because this suborder has some very sharply 



