MAMMALIA, 315 
e. Anterior limbs not adapted for flight; ulna and radius not united; 
hand normal; mamme usually abdominal. 
InsEcTivora, XLIX. 
ee. Anterior limbs adapted for flight; ulna and radius united; bones 
of hand and fingers much elongated, supporting a thin, leathery 
skin, extending along sides of body to the posterior limbs; 
mamme pectoral. . . . . + « « » CHropTerA, L. 
cc. Brain with a relatively large cerebrum overlapping much, or all, of 
the cerebellum and optic lobes. (Hducabilia.) 
J: Posterior limbs absent, the pelvis rudimentary; anterior limbs 
reduced to broad flattened paddles, without distinct fingers or 
claws; no clavicles; tail with a broad, horizontally placed 
caudal fin; cervical vertebrae more or less grown together; 
carnivorous. . “ . . Crrs, LI. 
Jf. Posterior limbs and rials well developed; anterior limbs with 
hoofs, claws, or nails. 
g. Femur and humerus not exserted beyond the common integu- 
ments of the body; clavicles more or less rudimentary; 
mamme abdominal or inguinal. 
h, Feet with hoofs; molars mostly with grinding surfaces; in- 
cisors various; no tusks; developed toes, 1 to 4; herbivor- 
Oise. 4 » . + « . Uneuuata, LIL 
hh. Feet with developed claws; canines specialized ; molars, 
one or more, sectorial, adapted for cutting; incisors §; 
carnivorous. . . , . . Ferra, LIT. 
gg» Femur and humerus exserted; “feet with distinct toes which 
are provided with nails ; clavicles present; an inner digit 
of hand (thumb) opposable to the others; orbits encircled 
by bone and directed forwards; mamme pectoral, two in 
number (rarely also an inguinal pair). Primarszs, LIV, 
Orpen XLVI MARSUPIALIA. (THE Marsvria.s.) 
Young developed without a placenta, and born at a very early 
stage and incomplete condition of development. The young at 
birth are usually placed in an abdominal pouch formed by a fold of 
skin about the milk glands of the mother, where they remain for a 
considerable time. Reproductive organs in both sexes of peculiar 
structure, nearly all the parts being double in the female. Skele- 
ton showing numerous peculiarities, the teeth usually more numer- 
ous than in the higher Mammals. Brain small, the corpus callosum 
rudimentary. Heart with two vene cave. This large group is 
chiefly confined to Australia. It represents an early or primitive 
type of Mammalia, which has now become extinct in most parts of 
the world. The single non-Australian family approaches most 
nearly to ordinary Mammals. (Lat., marsupium, pouch.) 
Families of Marsupialia. 
u. Tail long, prehensile, nearly naked; feet plantigrade, 5-toed, the first toe 
thumb-like and without claw; teeth 50. . . . Dipexrimpip#, 180. 
