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1848, gravid females were secured by searching hollow logs, trees, and 
burrows. 
Three females .were dissected at different stages of gestation. The 
young of one weighed two and one-half grains each; of another, three 
grains; and one specimen of the young of a third female, secured by a 
Cesarian operation at the moment when all the rest had been exuded, 
weighed four grains. The average weight is between three and four 
grains. 
The same author describes the young opossum as “little creatures that 
are nearly as well developed as the white-footed mouse and several other 
other species of rodentia. They are covered by an integument, nour- 
ished by the mamme, breathe through nostrils, perform the operations 
of nature, are capable of a progressive movement at the moment of their 
birth, and are remarkably tenacious of life, moving several inches on the 
table by crawling and rolling, and surviving two hours with the ther- 
mometer at 66° Fahrenheit.” 
The period of gestation is from fifteen to sixteen days—exactly tifteen 
in the case of one female under the personal observation of Dr. Michel, 
as recorded in the transactions of the Academy of Natural Science for 
April, 1848. 
The young are naked and flesh-colored, the eyes and ears covered with 
skin, through which the organs are visible. The mouth is a small orifice, 
just large enough to receive the teat, which is not much, if any, larger 
than the body of a pin. 
The body is half an inch long; the tail about one-fifth inch. The 
growth is rapid, the young increasing in a week from four to thirty 
grains, and in length nearly two inches. The teats of the mother, at this 
age of the young, are an inch long, much distended, and apparently 
drawn into the stomach of the young. 
At twelve days the eyes are not yet open; the ear-holes are apparenty 
and the nails visible and sharp. At four weeks the young at times let 
go the teat and protrude the head from the pouch, and a week or so later 
may be seen on the mother’s back, secured by winding their tails about 
their mother’s. | 
The mother defends them with courage, growling or snapping at dog 
or man she may meet with while traveling with her family in search of 
food. Some attach themselves to her back; others wind their tails about 
her legs; and so the family is dragged along. 
At this stage the young are well furred, and have a “mild, innocent 
look, and are sleek and in fine condition. Thisis the only stage in which 
the word pretty can be applied to the Opossum.” 
