m THE ORNITHORYNCHXJS PARADOXUS. 145 
individual portion of anatomical science to which the un- 
divided attention of that distinguished author has been 
directed. This observation will explain the brevity of this 
and the*succeeding Memoirs on the anatomy of the Orni- 
thorynchus, for most of the internal organs, which now fall 
to be described, have been already submitted by him to a 
minute dissection. 
It has been already remarked, that, properly speaking, 
there is no ascending branch of the lower jaw in the Orni- 
thorynchus, instead of which there is found only a slight 
curvature ; the coronoid process is small, though sufficiently 
distant from the condyle ; and the general disposition of the 
glenoid cavity, for receiving the condyle, seemed to me such 
as to admit of extensive motion from before, backwards, 
and also horizontally. This agrees with the configuration 
of the mouth and palate, and with the total absence of all 
cutting or incisive teeth. Whatever be the food swallowed, 
whether insects or aquatic vegetable matter, it must be sub- 
mitted to a certain degree of trituration in the mouth, and, 
to effect this completely, is conveyed into two large bag& 
or cheek-pouches placed on each side of the head, and the 
only entrance into which is between the large grinding- 
teeth. This was essential to the existence of the animal, 
and results from the structure of its stomach, which, being 
totally without that strong cuticle and powerful muscles by 
which the food is triturated in birds and some other animals 
(as in the Myrmecophaga capensis), required that the 
whole of the functions of mastication, the complete tritura- 
tion of the food, and its reduction to a pulpy mass fit for 
the immediate action of the gastric juices, should be per- 
formed in the mouth. The cheek-pouches, situated a little 
behind the angles of the mouth, are capable of containing 
a considerable quantity of food ; they are lined by a strong 
cuticle, and have posteriorly a gland, which evidently pours 
VOL. V, K 
