118 FAUNA AMERICANA. 



Habit. Manner of living analogous to that of 

 the martins, but inactive and nocturnal ; hiding 

 during the day in bushes, holes or branches of 

 trees ; feeding on birds, eggs, reptiles, insects and 

 fruit. Bringing forth a great number of young, 

 which at birth are yet in an embryotic state, with 

 only rudiments of limbs and tail, becoming im- 

 mediately attached to the teat of the mother by 

 the mouth, which bleeds when forcibly separated; 

 less than one fourth of an irxh long (in the opos- 

 sum,) at the period of birth, when until very late- 

 ly no traces of placenta or umbilical cord had 

 been discovered. M. E. Geoffroy de St. Hilaire, 

 (Annales des Sciences Nat. 1824,) has just an- 

 nounced the discovery of the vestiges of a placen- 

 tal organization, and of an umbilicus, observed in 

 a very small fetus of the " Didelphis virginiana.^' 

 These observations have served to enlighten a 

 most mysterious subject, and in the generation of 

 the opossum, brings us back to the more usual, 

 if not the more regular course of nature ; in com- 

 mon with other mammifera, these animals do in 

 fact pass through the various stages of gestation, 

 changing only their locality at different periods. 

 Thus they exist as ovum in the ovaries, em- 

 bryon in the uterus, and fetus in the pouch. This 

 interesting subject is as yet by no means divested 

 of obscurity. 



Inhabit all America. 



