of the Mammary Organs of the Kangaroo. (^Q 



panni cuius carnosus, posteriorly, and above to the tendon of the 

 external oblique muscle of the abdomen, while the lower and 

 lateral parts of the bag are attached to the mammary gland by 

 the medium of its connection with the teat, and to a muscle of 

 the gland by cellular tissue. This muscle of the mammary 

 gland, which has not hitherto been clearly or correctly de- 

 scribed, is situated immediately above the brim of the pelvis, 

 lying upon the external oblique muscle of the abdomen. It is 

 of a triangular shape, and is attached by a narrow origin to the 

 back part of the pelvis, from which point it passes transversely 

 round the lower part of the belly. In its course it expands, 

 and afterwards divides into two layers, an anterior and a poste- 

 rior ; between these the mammary gland is inclosed ; after which 

 the fibres of the muscle are continued onwards, and passing 

 forward, join with those of its fellow on the opposite side. The 

 pair of muscles, therefore, completely encircle the lower part 

 of the abdomen, inclosing and enveloping between their fibres 

 the mammary gland on each side {tab. 5. f. a.). Neither these 

 muscles nor the marsupial bones belong properly to the pouch ; 

 since the whole of the pouch may be removed from the abdo- 

 minal muscles without disturbing in the slightest degree either 

 the muscles I have just described, the glands themselves, or the 

 marsupial bones and parts connected with them ; the pouch 

 being, as I have already stated, nothing more than a fold or 

 duplicature of the skin, covered anteriorly by panniculus car- 

 nosus and common integument, and connected only by cellular 

 tissue to the abdominal parietes. 



The real use of the marsupial bones has not hitherto, I believe, 

 been clearly explained ; nor have I been able to meet with any 

 accurate anatomical description of these parts and their sur- 

 rounding connections : I consider it therefore necessary, before 



I state 



