1895.] AJfATOMl! OF PIPA AMEEICAJSTA. 837 



It is triangular in form and arises from the clavicle up to about 

 halfway up, and from the base of the scapula anterior to the 

 attachment of the clavicle. The fibres converge to an insertion 

 upon the humerus nearer to the shoulder-blade than that of the 

 deltoid. In Pipa the smaller head of the deltoid only arises from 

 the clavicle and does not reach the omosternum ; it may there- 

 fore rather correspond to the muscle just described in R. guppyi 

 than to the clavicular head of the deltoid of that frog and of Rana 

 esculenta. 



Pectoralis minor. This muscle, to which I provisionally give the 

 above name, is another muscle which is apparently absent from the 

 shoulder of Rana esculenta, as I can find no description of it in 

 Ecker. But it is present in Rana guppyi. It arises from the 

 coracoid, but from the lower part, not from the upper part where 

 the coraco-humeralis takes origin. It is, indeed, rather related to 

 the suhscapulans running parallel with that muscle, and indeed 

 partly covered by it for nearly the whole of its course, but every- 

 where separable from it. It is a fleshy muscle with fleshy origin 

 and insertion. At the insertion it bifurcates and is attached to 

 the humerus on either side of the tendon of insertion of the 

 posterior sternal portion of the pectoral. 



I find this muscle in Pipa, where, however, it is quite insig- 

 nificant compared with the large muscle of Rana guppyi ; it arises 

 from the lower portion of the coracoid, and is hardly distinguishable 

 either at its origin or insertion from the coraco-humeralis, except 

 that it is entirely fleshy, while the coraco-humeralis is inserted by a 

 strong tendon. 



Muscles of the Leg. 



"When the muscles of the thigh are exposed to view by removing 

 the skin, five muscles are visible on the ventral surface in Rana. 

 R. guppyi is precisely like R. temporaria. These muscles are, 

 commencing with the anterior border of the thigh, vastus internum, 

 sartorius, adductor magnus, rectus intemus major, and r. i. minor. 

 In a similar preparation of the corresponding region of Pi2)a it is 

 necessary, in order fully to display the muscles, to cut away the 

 origin of the rectus ahdominis; for this muscle in Pijja arises 

 from nearly the entire length of the femur, and naturally, therefore, 

 entirely hides the vastus intemus. When this dissection is 

 effected no less than seven muscles are visible, six of them for 

 nearly the whole of their course, as shown in the accompanying 

 drawing (fig. 4). 



But a very important muscle of the thigh of Rana is totally 

 wanting in Pijya — that is, the sartorius ; I could find no trace of 

 this muscle \ the absence of which is possibly to be accounted for 

 by the physical impossibilities introduced by the attachment to 

 the femur of the abdominal musculature. 



The adductor magnus is more completely divisible into two 

 parts than it is in Rana. In Rana the muscle is, as it were, split, 



* Mayer calls " sartorius" wbat I term sertiitendinosus (anterior head). ■ • 



