98 



MAMMALIA. 



the trouble to fix up their nesis at all. At such times they simply 

 crawl into any convenient shelter, without y;-atherinor so much as a 

 bunch of moss to soften their bed. Snow completes the covering, 

 and as their breath condenses and freezes into it an icy wall begins 

 to form, and increases in thickness and extent day by day till they are 

 soon unable to escape, even if they would, and are obliged to wait 

 in this icy cell till liberated by the sun in April or May. 



The diminutive size, premature appearance, and helpless condition 

 of the young of this species at birth cannot fail to excite surprise. 

 They are not six inches (i 52 mm) in length, weigh less than a 

 pound (453.6 grams), and are not yet covered with hair. Their eyes 

 do not open for more than a month. I know of no other mammal, 

 except among the Marsupials, whose young are so disproportion- 

 ately small, or are born in such an undeveloped condition. It is 

 necessary for their preservation that the mother should cover them 

 nearly the whole time for the first two months. 



Mr. Frank J. Thompson, Superintendent of the Zoological Garden 

 at Cincinnati, has })ublished a thoroughly trustworthy account of the 

 early development of a litter of Black Bears, in confinement; and 

 observations of this nature are so rare that I here reproduce the 

 main part of his communication : 



" About the middle of January last, the female Black Bear in the 

 Society's collection refused to come out of her den into the open pit 

 and would not allow the male to approach her. She was immediately 

 closed in and furnished with an abundance of hay, with which she 

 busied herself in making a nice warm bed. At 4 p. m. on January 

 26th, the vouncr ones were born and I did not see them until the 

 third day after, when I was surprised by the keeper informing me 

 that she would allow him to enter the den. On going with him, he 

 unlocked the door, fearlessly walked in, and quickly began feeding 

 her with bits of bread, which he sliced from a loaf held in his hand. 

 By holding the bread just over her head, he finally tempted her to 

 sit up on her haunches, when I obtained a clear view of the two 



