Family DIDELPHIDAE 45 



koala pictured on Australian stamps. Marsupials are most abun- 

 dant in Australia and neighboring islands, but they have many 

 representatives in South and Central America. The range of one 

 species, the opossum, includes much of the United States. 



Economic Status. — In Illinois the opossum is trapped for 

 fur and, to some extent, for food. For both food and fur the 

 monetary value is low. The opossum is beneficial in that it eats 

 some injurious insects, but it may at times be harmful to wild 

 birds and cause loss to farmers by eating poultry and eggs. 



DIDELPHIS MARSUPIALIS Linnaeus 

 Opossum Possum 



Description. — The opossum, fig. 42, is as large as the aver- 

 age domestic cat. Its face is long and subconical, its ears are 

 naked, its tail is scaly and almost bare, and its feet are decidedly 

 handlike. The female has on her abdomen a woolly pouch in 

 which she carries and nourishes her newborn young. The 

 possum's face is whitish, its eyes are beady black, and its bare 

 ears are shiny black, mottled with pink or white. Its feet are 

 black, and its toes are pink or white. The inner toe of each hind 

 foot is thumblike, fig. AOa. 



The hair making up the dense woolly underfur of most opos- 

 sums is creamy white, with grayish tips, and the long, guard 

 hairs are dark gray or black. This combination gives the body a 

 general grayish appearance. However, in many specimens the 

 underfur is tipped with brown, which, showing through the 

 guard hairs, gives the body a brown instead of a gray appear- 

 ance. A few individuals are almost entirely black, and others 

 are a very pale gray or nearly white. In the occasional true 

 albino, the general color is ort-white, the ears and feet are 

 white, and the eyes are red. Some very light gray individuals 

 may resemble albinos but in these the eyes, ears, and feet have 

 the normal black coloration. 



Length measurements: head and body 17-21 inches (430-530 

 mm.); tail 8^-12^2 inches (220-320 mm.); over-all 25i/i- 

 331^ inches (650-850 mm.); hind foot 2^^-3i^ inches (60-80 

 mm.); ear 2]4-2]/2 inches (57-66 mm.). Weight (adults, Illi- 

 nois) : 6-12 pounds. 



The opossum skull, 100-125 mm. (4—4% inches) long, can be 

 distinguished from the skulls of other Illinois mammals bv the 



