186 POUCHED MAMMALS 
Of these eight Families, only two, the first and seventh, 
will be specially noticed. 
Marsupials are distinguished from all other mammals by 
the fact that the female possesses in the skin of her abdomen 
a large, flexible pocket, or pouch, in which the nursing glands 
are situated, and in which the young are carried for a time 
after birth, until more fully developed. They differ from 
ordinary mammals in being without what is called a pla-cen’ta, 
which is an arrangement of veins by which the blood of the 
mother circulates through the veins of the unborn young. 
In other words, in a marsupial, the blood of the mother does 
not circulate through the veins of the unborn young. As a 
result, at the time of its birth, the young marsupial is a 
tiny creature, hairless, blind and utterly helpless. Even the 
young of a large kangaroo looks more like a little lump of 
jelly than a highly organized living creature. One which I 
saw in the London Zoological Gardens was less than an inch 
in length, and no thicker than a lead-pencil. 
The newly born young is taken by the mother, in her 
front paws, and placed in her pouch; and the half-formed 
creature, with a mouth specially formed for suction, attaches 
itself to the nursing gland, and so remains for many days, or 
even weeks, Slowly it grows, until it develops hair, and its 
eyes open. At length it becomes large enough so that it 
ventures to stick its little head out and view the world. By 
and by it climbs out to take exercise, but jumps back again 
at the first alarm. In an animal which travels as far each 
day as the kangaroo, a pouch for the conveyance of the young 
is a great corivenience. 
