of the Mammary Organs of the Kangaroo. 463 
that from these alone does the future young receive nourish- 
ment; that each of the four teats exists prior to its external 
appearance in the form of a follicular membranous canal, ter- 
minated by a projecting nipple, which becomes everted and 
protruded from its imbedded situation in the mammary gland, 
to form a permanent medium of communication between the 
mouth of the young and the secreting gland from which its 
nutriment is derived. 
EXPLANATION OF TAB. XXVI. 
Fig. 1. A view of the interior of the pouch of a young kangaroo, 
showing the four follicular apertures through which the 
future teats are protruded. 
Fig. 2. Dissection of the mammary organs of the same, disi 
the glands, membranous canals, and imbedded and unde- 
veloped nipples. 
VOL. XVI. 30 XXV. On 
