686 PKOFESSOE OWEX ON THE ECHIDXA HYSTEIX. 
PLATE XLI. 
Fig. 1. Female organs of Echidna HystrLv; letters explained in the text. 
Fig. 2. Section of uterus : magnified ; ditto. 
Fig. 3. Young of Echidna HystrLv : twice nat. size ; ditto. 
Fig. 4. Ditto: mouth and end of upper jaw: five times nat. size: — a, nostril; e, inter- 
narial tubercle ; m, upper lip ; n, lower lip ; l 9 tip of tongue. 
Fig. 5. Young of Omithorhynchus paradoxus: — «, nostril; b, eye-orifice; c, ear-orifice; 
e, internarial tubercle ; relatively smaller than in fig. 3, as being in progress 
of disappearance in a more advanced young one. 
