TEETH AND CLASSIFICATION OF MAMMALS, 
17 
The central case of the bay contains a collection illiistrat- Teeth of 
ing the principal characters of the teeth in the Mammalia. 
Its inspection should commence at the north-east corner, where 
the visitor will find himself after completing the survey of the 
osteological specimens in the wall-cases. In the first division 
specimens are placed showing the general characters of 
teeth, their form, the different tissues of which they are 
composed, the two great types of dentition in mammals, 
homodont and heterodont, the nomenclature and homologies of the 
different teeth, and their development and succession. The 
principal modifications of teeth according to function are next 
shown by examples of forms adapted for fish-eating, flesh- 
eating, insect-eating, grass- eating, &c. The remainder of 
the case is taken up by examples of the dentition of the 
different families of mammals arranged in systematic order, 
prepared so as to display not only the shape of the crowns, but 
also the number and character of the roots by which they are 
implanted. 
In bay E"o. II. the two wall-cases contain a collection arranged Bay ii. 
, 1 . i- 1 4-1 n • T Classification 
to show m a synoptical manner the generally recognised of Mammals. 
orders and sub-orders of existing Mammals, by examples 
selected to illustrate the predominating characters by which 
these are distinguished. A brief popular account of the 
characteristics of the group, and a map showing its geographical 
distribution, is placed with each. This is intended not only for 
an introduction to the study of the class by visitors to the 
museum, but also as a guide to a method of arrangement which 
may be adopted in institutions with limited resources. 
Among the illustrations of the order Primates is placed the 
skeleton of a young Chimpanzee dissected by Dr. Tyson, 
which formed the subject of his work on the " Anatomy of a 
Pigmie," published in 1699, the earliest scientific description 
of any man -like ape. 
The central case of this bay contains illustrations of the integument 
outer covering or integument and its modifications in the class 
of Mammals, divided into the following sections : 
1. Expansion of skin to aid in locomotion, as the webs 
between the fingers of swimming and flying animals, the para- 
chutes of flying animals (fig. 2). 
c 
