184 Prof. Owen on the Class Mammaiia. . 
terized is called ‘MoNnoTREMATA,’ in reference to the single ex- 
cretory and generative outlet, which, however, is by no means 
peculiar to them among Mammalia. e Monotremes are insec- 
e reduc- 
stru 
tion of the food to small particles by acts of rapid and continued 
the order. The orbits are not 
* “ Outlines of a Classification of the Marsupialia,” Trans. Zool. Soe., vol. i, 186% 
+ For other Osteol ical and Dental Ghathidertelin of the Marsupialia, | oe 
bee above cited, and that “On the Osteology of the Marsupialia, Trans. 
vol. ii, p. 379 (1888). 
