167 



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 

 Csesarian 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 mammae, breathe through nostrils, perform the operations 

 of nature, are capable »f 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 fifteen 

 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 apparent, 

 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 theii* 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. This is the only stage in which 

 the word pretty can be applied to the Opossum." 



