668 
VERTEBEATA. 
THE OPOSSUM AND HEE YOUNG ONES. 
are able to move about. At tbe age of four M^eeks they occasionally leave the nipple and may be 
seen peeping out of their sack ; a week afterward they venture forth, but keep close to the mother, " 
and hold on to her by their tails. Sometimes with a dozen young ones of the size of rats, thus 
clinging around her legs, neck and body, and some of them dragging along on the ground, she 
may be seen going about in search of food. At this age these animals are pretty. They remain 
with the mother till about two months old ; they then learn to take care of themselves, but con- 
tinue in the vicinity, seeming still to be under maternal guardianship in a certain degree. Mean- 
CEAB-EATINO OPOSSUM. 
time another breed is produced, and during the season a third, and some of all these may be seen 
at once with their prolific parent. In winter, if the climate is cold, the opossums become sluggish, 
but not torpid like the woodchuck. They are common in all the Southern and Southwestern 
States, and in California and Mexico. They are also found in the Middle States as far north as 
Pennsylvania, and sometimes in New Jersey. 
This is the only animal of the kind known in the United States; in South America there are 
