286 



the entrance of the preservative fluid, but the viscera were not 

 in a good condition for examination, either microscopic or macro- 

 scopic. 



Female Organs of Reproduction. 



Marsupium. — In my previous description of Notoryctes I re- 

 ported that an examination of the specimens obtained on my 

 transcontinental journey enabled me to establish the fact of the 

 existence of a pouch in the female, thus confirming statements 

 which had been made by my local informants, and verifying the 

 somewhat uncertain conclusion to which the examination of the 

 first imperfect specimen liad led. A more careful investigation 

 of the organ enables me now to supplement my previous remarks 

 with additional particulars. As stated, the furthest anterior 

 limit of the fundus of the pouch, which opens backwards, and 

 readily admits a rod 5 mm. in diameter, is 15 mm. in front of the 

 cloacal orifice, but its true depth, i.e., the extent covered by the 

 ventral wall, is S mm. Long sparse reddish hairs cover the 

 greater part of the interior, v/ith which are interspersed numerous 

 grains of red sand, and from its mouth a shallow groove, as 

 already mentioned, leads backwards to the cloacal aperture. The 

 fundus is not, however, a simple rounded cid-de-sac, but extends 

 laterally into two shallow bays or recesses, in each of which lies 

 a bundle of stiff almost bristle-like hairs ; these were either lying 

 completely loose, or were so feebly attached that they came away 

 on the slightest touch of the forceps. On the dorsal wall of the 

 pouch, at the entrance of each of these small bays or recesses, 

 and 2 mm. from its blind extremity, is a very slightly elevated 

 oval, or nearly circular, mammary prominence, having a diameter 

 of from 1 mm. to IS mm., its surface being devoid of hair. A 

 distance of 2 mm. separates these two mamnue. They are so small 

 as to be scarcely visible without a hand lens, and only come into 

 view when the pouch is completely laid open. Rising from a 

 slight depression in the centre of the prominence is an exceed- 

 ingly minute nipple-like projection, which, however, scarcely 

 reaches beyond the general level of the surface of the mamma. 

 The arrangement may be likened to that of a circumvallate 

 papilla, with a shallow sulcus, or to a retracted human nipple iii 

 extreme miniature. 



A series of microscopic sections proves conclusively that the 

 prominence is the outward expression of a mammary gland, and 

 that the minute papillary projection is a nipple. Some of the 

 sections which have passed through the latter, vertically to its 

 exposed surface, show three or four nearly straight and parallel 

 ducts of exit, while in the tissues below is evidence of the existence 

 of glandular alveoli, milk-tubules and ducts. Many large empty 

 hair follicles are also seen in the sections, in connection with 



