1896.] kVotoGY OF iiODBNTS. 189 



11. The gracilis is usually double in the Myomorpha, single in 

 the Sciuromorpha. 



12. The accessorius is usually absent in the Myomorpha, always 

 present in the Sciuromorpha. 



With a view to comparing the myology of the Lagomorpha with 

 the other suborders, I dissected the muscles of a Hare and a Eabbit, 

 but have refrained from enlarging this paper with a detailed 

 description of these muscles because they have already been 

 described by other authors. 



Differences betiveen the Myomorpha and the Lagomorpha. 



1. In the Myomorpha the different parts of the temporal are 

 closely connected. In the Lagomorpha the orbital part is large 

 and much separated from the rest. 



2. In the Myomorpha the anterior deep part of the masseter 

 passes through the infraorbital foramen. In the Lagomorpha 

 there is no anterior deep part. 



3. The posterior belly of the digastric is well marked in the 

 Myomorpha, in the Lagomorplia it is only present as a narrow 

 tendon. 



4. The transverse mandibular muscle is present in the Myo- 

 morpha, absent in the Lagomorpha. 



5. The omo-hyoid is present in the Myomorpha, absent in the 

 Lagomorpha. 



6. The acromio-trachelian (levator claviculae) rises from the arch 

 of the atlas in the Myomorpha. In the Lagomorpha it rises from 

 the basioccipital and bifurcates below, one part going to the meta- 

 cromion, the other to the clavicle and deltoid. 



7. The scalenus anticus is sometimes present in the Myo- 

 morpha but absent in the Lagomorpha. 



8. The scapulo-clavicuhiris is absent in the Myomorpha, except 

 the Bathyerginje. It is present in the Lagomorpha. 



9. The three parts of the deltoid are fused in the Myomorpha, 

 separate in the Lagomorpha. 



10. The biceps cubiti has two heads in the Myomorpha, one iu 

 the Lagomorpha. 



11. Among the Myomorpha the rotator humeri is only present 

 in the Cricetinoe. In the Lagomorpha it is present in both rabbit 

 and hare. 



12. The pronator quadratus is present in the Myomorpha, 

 absent in the Lagomorpha. 



13. The clavo-cucullaris part of the trapezius is generally 

 present in the Myomorpha, absent in the Lagomorpha. " ; 



14. The splenius colli is absent in the Myomorpha, present in 

 the Lagomorpha. 



15. The rectus abdominis frequently decussates with its fellow 

 of the opposite side in the Myomorpha. In the Lagomorpha 

 there is no decussation and the lineas transversee are much better 

 marked. 



