52 
ZOOLOGICAL LITERATURE. 
or even approaching black, but nearly always uniform according to the va- 
riety; no silvery grey tint. Skull from 7 to 8 inches long; nasal bones 
relatively broad to their length ; supratympanic cavity moderately deep; 
postpalatine foramina triangular, largo ; scapula broad as compared with its 
length. 
/3. Lasiorhinus (Gray). Fur smooth and silky; muffle hairy; incisors 
much curved, forming nearly a semicircle ; the enamelled surface directed 
nearly forwards. Dorsal vertebrae 13 ; ribs 13 ; lumbar vortebiw 6. Skull 
broad in proportion to length ; nasal bones relatively very broad ; frontal 
bones broad, presenting a well-marked supraorbital ridge and postorbital pro- 
cess ; supratympanic hollow, very large ; foramen magnum oval ; transverse 
processes of caudal vertebrie short and narrow. — With one species : Phasco- 
lomys latifrons (Owen, Angas, M‘Coy) = P. lasiorhinus (Gould) =^Jjasio7'hinus 
m‘coyii (Gray), p. 854, pi. 47. Size about equal to that of P. toomhat, but 
body longer. Fur of a light silvery mouse-colour, with mottled, darker, buff 
and purplish hairs ; muffle broad, white, and hairy ; ears large, prominent, 
and acutely pointed; white spot above each eye ; chest, neck, and inside of 
fore limbs whitish ; rump of a rufous tint. 
Phascolojnys lasiorhinus [latifrons'], fig. in Zoolog. Sketch, by Wolf and 
Sclater, vol. ii. 
Mao'opus t'ufus, fig. in Zoolog. Sketch, by Wolf and Sclater, vol. ii. 
Pteroyale longicauda, sp. n., Krefft, Proc. Zool. Soc. 1866, p. 324, from New 
South Wales. 
MONOTREMATA. . 
Our knowledge of the history of propagation of the Monotre- 
mates has been much advanced by a memoir of Prof. Owen in 
Philos. Trans. 1865, pp. 671-686, in which he publishes his dis- 
covery of a pair of marsupial pouches in the impregnated female 
of Echidna hystrios : — r 
The specimen was caught in August, with one of the mammary foetus at- 
tached to it, and sent to Dr. F. MUller in Molboiinio, who forwarded it to 
Prof. Owen. The pouches were small, half an inch in depth and two-thirds 
of an inch in length of aperture, and so well concealed by the hair that they 
were not perceived by the gentleman in Australia who examined the animal. 
At the fundus of each pouch is an elliptic surface, about four lines in diameter, 
on which the orifices of about 60 ducts of the mammary gland can be dis- 
cerned. There is no nipple to which the foetus hangs, as in Marsupials ; and 
it is evident that the young simply nestles itself within the marsupial fossa, 
clinging, perhaps, by its precocious claws to the skin of that part. The foetus 
obtained was little more than one inch long, and found dead and detached 
from the mother on the fifth day of her captivity ; it is probable that the 
other pouch was occupied by a second foetus, but that this was lost at a some- 
what earlier period. 
There is no trace of such pouches in immature or uuimpregnated females^ : 
* The change in the development of the egg-pouches of Nototrema is an 
example perfectly analogous to this observation. 
