32 



CLASS MAMMALIA. 



ORDER-M ARSUPIALA. 



3. CHEIRONECTES (Gr. x'V- a * an ^ ^ y 1 KT *lf< a swimmer)- Incisor 

 teeth, above ten, below eight ; cuspidated teeth longer than the incisors ; 

 muzzle sharp : face hairy ; eyes lateral ; ears naked and round ; tail scaly 

 and voluble ; feet distinct, pentedactylous, and the toes connected by webs ; 

 thumbs on the hind feet; nails hooked on the fingers and toes, but wanting 

 on the thumbs. 



1XSECTIVORA. DESCRIPTION OF SPECIES. 



DIDELPHTS Opossum. The Didelphides differ from the Cheironectes, 

 in not having the feet webbed ; from the Dasyuri, in having the tail pre- 

 hensile and naked, and more teeth ; and from the Phdangista, in having 

 all the toes distinct from each other, and unconnected by skin. 



Some of the genus possess an abdominal pouch, in which their young 

 are carried ; but others have only a fold of skin on each side of the bottom 

 of the abdomen, forming as it were the rudiment of a pouch, and are said 

 to carry their young upon their back : this circumstance has led to their 

 division into two snbgenera, and indeed some naturalists have divided them 

 into distinct genera. Their tail is very long and prehensile, so that they 

 are able to swing themselves from tree to tree like the Monkeys. 



The Opossums are fetid, nocturnal animals, which move but slowly, and 

 are great enemies to poultry and birds, the eggs of which, as well as the 

 birds, they destroy ; they live also upon fruit and nuts, and are omnivorous 

 feeders. All are natives 

 of America. 



The mode in which the 

 young animal is conveved 

 into the abdominal pouch 

 of the parent is not at all 

 understood, as they have 

 not been known to breed 

 in confinement. This bag 

 is proper to the female, 

 which, after the birth of 

 the young, and their intro- 

 duction into the pouch, 

 closes it so firmly that it 

 cannot be opened without 

 the greatest difficulty : this 

 power depends upon cer- 

 tain muscles attached to 

 the bones which support 

 the pouch laterally. 



1. Opossums with pouches. The Virginian Opossum (D. Virginiana), 

 about the size of a Cat, but of a thicker form ; the fur of a dusky white 

 colour, composed of woolly hair, like felt ; ears thin, naked, and black, 

 edged with white ; head nearly entirely white ; tail about thirteen inches 

 long, covered with dusky hair at its root, but the remainder naked and 

 covered with a scaly skin resembling the tail of a Snake, and prehensile ; 

 legs short ; feet armed with claws, which are sharp, except the innermost, 

 which is rounded like those of the Monkeys; belly whitish, and in the 

 female thirteen teats, of which twelve are disposed in a circle, and one in 

 the centre. It lives in the woods and fields, but at night sallies out in 

 search of its prey, which consists of poultry and their eggs ; but it also 

 feeds upon fruits and roots. Its gait is very slow ; but, like the Monkeys, 

 it is very ready in getting from the branch of one tree to another, by means 

 of its prehensile tail. The young ones when first littered are said not to 

 weigh more than a grain, and become firmly attached to the teat, upon 

 which they grow ; and when they have acquired the size of a Mouse, which 

 is about the fiftieth day, they leave the pouch, but quickly return to it on 

 the slightest alarm ; and they do not entirely leave it till they have acquired 

 the size of a Rat. They go with young about twenty -six days. Native o'f 

 America. (Plate 10.) 



The Cayenne Opossum (D. Marsupialis), in size resembling the pre- 

 ceding, but the snout is longer, the mouth wider, and the skin of a vellowish- 



Opossum. 



brown colour. It is made use of as food, being considered delicate 

 eating. 



The Molucca Opossum (D. Opossum). This species, which is not so 

 large, is considered by Dr. Shaw as a variety of the preceding ; but it has 

 been described as distinct by Daubenton. It is a native of the hot countries 

 of South America. 



2. Opossums with a longitudinal fold of skin on eacli side of the belly. 

 The Naked-tailed Opossum (D. Nudicaudata), about the size of the Molucca 

 Opossum, and nearly resembling it in colour : is a native of Cayenne. The 

 Large-tailed Opossum (D. Crassicaudata), a native of Paraguay, The 

 Mexican Opossum (D. Cayopollin), which is about nine inches in length ; 

 the Woolly Opossum (D. Lanigera), the Mwine Opossum (D. Murina), an 

 animal of a small and slender form, known as the Wood Rat. The Touan, 

 (D. Tricolor), the Short-tailed Opossum (D. Brachyura), and the Dwarf 

 Opossum (D. Pusilla), which is only about the size of a Mouse. 



PERAMELES. All the animals belonging to this genus are natives of 

 Australia; they are carnivorous, live in burrows which they dig with their 

 fore feet, and move by a succession of leaps. 



The species are The Porculine Opossum (P. Obesula), which is about 

 the size of the Common Rat; the head rather short and the forehead 

 arched ; the ears larger and rounded ; in both jaws eight incisive teeth ; 

 the upper parts ferruginous-yellow, and the under white. Of this species 

 Geoffroy has more recently made a distinct genus on account of the equal 

 number of incisive teeth, which, however, seems scarcely sufficient cause 

 for the separation. (Plate 10.) 



The P. Nasuta is sixteen inches long ; the P. BougainviClei is but six 

 inches in length, while the P. Lawsonii is two feet. 



CHIRONECTES. The Loutre de la Guiane (C. Guianensis) is a little 

 bigger than the Field Mouse. This animal is brown above, with three 

 transverse greyish lines, broken in the middle, white below. Illiger has 

 separated it from the genus Didelphis, on account of the feet being webbed. 



Family FRUIT-EATERS ; Frugiwra. 



Genus. Species. Common Name. 



Phalangista - - - Gliriformis - - - Mouse-like I'halanger. 

 Another Genus of this family : Petaurista. 



CHARACTERS OF THE GENERA. 



1. PHALANGISTA (Gr. ^a\ay, a joint). Head roundish, muzzle 

 sharpish ; incisive teeth in the upper jaw six, of which the middle two are 

 long, narrow, and converging, and those on the sides very small, but the 

 hindmost the largest; in the lower jaw two, twice as long as the middle 

 upper teeth, inclined forwards and cutting ; cuspid teeth two in the upper 

 jaw, and instead of them in the lower, two or three little rudimental teeth, 

 often not penetrating the gum ; molar teeth in the upper jaw six, the first 

 very small, and resembling a cuspid tooth, the second large and pointed, 

 the four others tuberculated ; in the tower jaw five molars, of which the 

 first resembles the second upper, and the remaining four correspond to 

 those above ; ears short, or of moderate length ; feet five-toed, the front 

 toes disposed in a semicircle, and armed with strong, compressed, and sharp 

 claws ; the inner hind toe free, answering to a thumb, but nailless, the 

 next two shorter than the others, and covered with skin to the last joint, 

 so as to appear externally but a single toe with two claws ; the outer two 

 toes large ; tail prehensile, in some covered entirely with hair, except just 

 at the under part of the tip, but in others naked, and covered with 

 rugosities. 



2. PETAURISTA (Gr. viTavpov, an instrument to throw stones, because 

 the animal darts from branch to branch, as if shot from an engine). In- 

 cisive teeth, in the upper jaw six, of which the middle two are large and 

 converging, in the lower jaw two, inclining forwards ; no cuspid teeth, eight 

 molar in the upper and seven in the loner jaw on each side, the anterior 

 four upper and three lower conical, unequal, and rwonbtbg cuspid teeth, 

 the other four tubercular ; muzzle sharp ; eyes prominent ; ears hairy ; 



