1894.] 



MYOLOGY OP RODENTS. 



275 



the fibres of this converge to be attached to the acromion and spine 

 for a variable extent, as well as to the fascia of the outer side of 

 the arm and the pectoral ridge of the humerus. In the Caviidse 

 these fibres to the arm are specially well developed, and in Ceredon 

 some of them extend as far as the internal condyle. 



The abdominal panniculus divides about the lateral line of the 

 body into a superficial and a deep layer, which, as they approach 

 the ventral region, embrace the pectoral, the superficial fibres 

 passing over the muscle to be lost on its surface, the deep being 

 attached to the cartilages of some of the true ribs close to the 

 sternum and deep to the pectoral 1 . Posteriorly the panniculus 



Tig. 10. 



s Spine o{ scapula. 



Panniculus of Hystrix cristata. 



ends in a fairly Avell-defined margin over the gluteal muscles ; the 

 fibres of this part running round to the front and inner side of the 

 thigh to terminate in the fascia there. I have never seen any 

 attachment to the femur. Over the inguinal region there are 

 several planes of fibres ; some of these unite in the middle line 

 under the ventral surface of the penis, forming a sling to keep that 

 organ close to the body ; this arrangement is well seen in Codogenys. 

 The ventral and lateral parts of the panniculus of the body are 

 supplied by the great internal anterior thoracic nerve, which runs 

 back from the internal chord of the brachial plexus : the cervical 

 part is supplied by the superficial cervical and facial nerves. 



Latissimus Dorsi. — The latissimus dorsi rises from a large number 

 of the posterior thoracic spinous processes, the posterior three or 



1 See author's contribution to Proc. Anat. Soc, printed in the Journal of 

 Anatomy, xxvi. p. x (1892). 



