338 MAMMALS 



highly developed eyes, yet they are so adapted to nocturnal 

 flight, because of the great development of the tactual sense 

 in the wing membranes, that they easily avoid the objects 

 in or near their path. Indeed, it is said, they could do this 

 were they totally blind. Again, in most mammals, we find 

 the hind pair of legs the stronger ; but in the bats, the front 

 pair is the stronger and better developed, which is a direct 

 adaptation for flight, since it is these that are mainly con- 

 cerned in flight. 



Instances of adaptations among the mammals are almost 

 without end, and our space forbids mention of more. 

 Much pleasure and profit may be derived from a study of 

 the habits of mammals and of the adaptations to meet the 

 demands of their environments. 



CLASSIFICATION OF THE EXAMPLES 



Class — Mammalia. 



Subclass I — Prototheria. 



Order — Monotremata. 

 Types of Order. 



Ornithorhynchus anatinus — • Duckbill. 

 Tachyglossus aculeatus or Echidna aculeala 

 — Spiny ant-eater. 

 Subclass II — Theria. 



Section A — Metatheria or Marsupialia. 

 Order — Polyprotodontia. 

 Type of Order. 



Didelphys virginiana — Opossum. 

 Order — Diprotodontia. 

 Type of Order. 



Macropus giganteus — Kangaroo. 

 Section B — Eutheria. 



Order — Edentata. , 

 Types of Order. 



