900 ME. F. E. BEDDARD ON THE ANATOMY [DeC. 15, 



the skin itself and entirely from the skin, not merely by a few 

 fibres here and there as may be the case towards the middle line 

 of the body. 



The 2)ectorcdis cutaneus is completely absent. The septum which 

 divides the thoracic from the ventral lymph-sac runs across the 

 pectoralis sternalis at about its middle ; but I observed no trace of 

 the muscles in or about this septum which are so obvious in Bana. 

 These muscles would appear to be not unf requently unrepresented 

 among the Batrachians. In the present species they can haitlly 

 be represented by the cutaneous fibres of the outer pai-t of each 

 pectoralis abdominis described above. 



The sterno-radicdis, as in Bcma, arises from the omosternum, 

 and its origin is limited to the omosternum. Instead of being 

 overlapped by, it overlaps the anterior part of the pectoralis 

 sternalis. It is a broadish strap-shaped muscle, but not relatively 

 so large as in Raaa. 



The pectorcdis sternalis is divided, as in Rana, into a 2^07'i'^o 

 anterior and a portio posterior. The first of these two halves of 

 the muscle is not visible superficially for the whole of its extent. 

 Only a small pai-t appears before any dissection is made, as may 

 be seen in the text-figure accompanying this description (text- 

 fig. 176, p. 899), The origin of most of it underlies the origin of 

 the sterno-radialis, and some underlies the oi'igin of the pectoralis 

 posterior. The latter is a very large and deep fleshy muscle, 

 much larger than the portio anterior. It is triangular in form 

 and overlaps, as already stated, a pai't of the portio anterior. 

 Thei'e is a tendinous seam running along it for about half of its 

 course before I'eaching the humerus, on to which a part of the 

 pectoralis abdominis is inserted. The muscles of the two sides of 

 the body meet at a tendinous seam from which they chiefly 

 arise, but they take origin also from the very obliquely set 

 coracoids. 



Coraco-humeralis and p)ectoralis minor. — There are in Hemisus 

 three strong and fleshy muscles which correspond, as I presume, to 

 the two muscles thus named in Bavia [B. gup'jjyi *) to their origin 

 from the coracoid ; they lie one behind the other. The most 

 posterior of the series (text-fig. 177, p.) is quite visible superficially 

 before any dissection of the ventral musculature is made. It is in 

 contact with, but obviously separate from, the pectoralis sternalis 

 posterior. In section the muscle is at first crescent-shaped, since it 

 partly underlies, as well as being parallel to, the part of the 

 pectoi'alis already referred to. Further on the muscle becomes 

 flatter, and is inserted upon the humerus by a flat strap-shaped 

 short tendon immediately ventral of the insertion of the pectoralis 

 abdominis. It may be that this muscle is really referable to the 

 pectoralis sternalis rather than to the coraco-humeralis ; but in 

 any case it is perfectly distinct from the pectoralis from origin to 

 Insertion. 



* See Beddard, " Anatomy of Fipa," P. Z. S. 1895, p. 837. 



