266 - ZAGLOSSUS. 



a common insertion at the mastoid region just dorsal to the external ear and 

 posterior to the insertion of the sternomastoid. 



Beneath the splenius, and covering the back of the neck is the hiventer 

 cervicis, a broad muscular sheet, arising from the spines of the first thoracic and 

 all the cer\-ical vertebrae. It inserts by tendinous fibers along the dorsal part 

 of the occiput corresponding to the lambdoid ridges. 



The rectus capitis posterior minor is quite as large as the preceding and arises 

 from the anterior margin of the atlas, dorsal to the transverse process. Accord- 

 ing to Fewkes, its origin in the Echidna is from the posterior rim of the atlas. 

 In both it passes forward as a thin sheet to insert upon the posterior part of 

 the occiput, somewhat ventral to the insertion of the hiventer cervicis. 



The rectus capitis posterior major was not identified, although it is said to 

 be present in the Echidna as a very small muscle from the anterior extremity 

 of the spinous process of the axis to the occiput. 



The obliquus inferior originates from the lateral surface of the spine of the 

 axis and passes forward as a strong muscle to insert into the dorsal part of the 

 lateral process of the atlas. 



The obliquus capitis superior is a short thick muscle, from the ventral side 

 of the transverse process of the atlas to the occiput. 



The rectus capitis lateralis lies just ventral to the last, and arises from the 

 anterior face of the lateral process of the axis. It passes forward as a stout 

 round muscle to insert just lateral to the insertion of the obliquus superior. 

 Mivart states that in the Echidna this muscle has the usual relations, i. e., from 

 the atlas to the occiput, but in the Proechidna its origin is certainly from the axis. 



The longus capitis arises from the ventral side of the transverse processes of 

 the sixth and seventh cervical and first dorsal vertebrae. It passes forward 

 along the side of the neck as a ribbon-like band, that becomes a flat tendon 

 at the region of the axis and inserts into the jugular process of the skull, just 

 posterior to the tympanic bone. 



The scalenus is sunilar to that of the Echidna, arising from the transverse 

 process of the second to seventh cervical, and inserting on the first rib. 



Caudal muscles. — The dorsal muscles of the tail are so intimately con- 

 nected that they are with difficulty separated into distinct bundles. 



The portion corresponding to the extensor caudae medialis is of muscle fibers 

 from the spines and dorsal surfaces of the last two lumbar and the succeeding 

 vertebrae, and from the medial edge of the ihimi; from this muscle mass, tendons 

 pass to the articulating processes of the vertebrae. 



