:874 ANATOMY AND DKVKLOPMENT OF MARSUPIALIA, 



been dead for two days. Tlie pouch-young were fixed entire in 

 ■corrosive- sublimate- acetic-solution, the genital organs of the 

 mother in picro-sulphuric solution. In this latter case, on 

 sectioning, it was found that what blood there was in the vessels 

 had hardened so much, that it was only with extreme care and 

 difficulty that sections could be cut at all. The hopeless gapping 

 of the razor-edge, with consequent damage to the sections, is well 

 indicated in Fig. 10. 



The present j^aper consists of two parts. One is a description 

 of the genital organs of a pouch young measuring 65 mm. in 

 greatest length, not meant to be exhaustive, but merely for com- 

 parison with the adult organs; the other contains an account of 

 the adult genital organs. 



i. On the Genital Organs of a 65 mm. Poucii-Young of 



SaRCOPUILUS SATAN ICUS. 



External features of eynbryo. — Measurements: H.L, 33'5mm.; 

 «nout to root of tail (along dorsal curvature) 90 mm.; tail 20'5mm.; 

 arm 25 mm.; leg 21 mm.; foot 10mm. 



Body seemingly naked, but really covered with minute, very 

 fine hairs; of the general body-hairs those on top of the head, 

 snout, and back are rather longer than others. There are well 

 •developed vibriss£e(8 mm. in length); there are about eight strong 

 hairs above the eyes, and twenty in a patch below and behind 

 them. On the shut and united eyelids, eyelashes are fairly well 

 developed. A small bundle of eight or nine specialised hairs is 

 placed on a small elevation on the posterointernal side of the 

 arm. The leg is devoid of special hairs. The lips are quite 

 united, as well as the eyelids. The ear-pinna is quite free, and 

 directed backwards. The umbilical scar is almost obliterated. 

 The marsupium consists of two contiguous deep sacs, with teat- 

 rudiments. Clitoris visible, and external. Limbs well developed; 

 fore-limb with five clawed digits, first shortest, third and fourth 

 longest, second and fifth equal and intermediate; hind-limb with 

 four equal toes. 



