356 NATURAL HISTORY. 
may notice in this connection, in the insect world, the 
special provisions against the cold in the cocoons which 
are to remain through the winter to another season 
($ 413). 
620. The individual adaptations seen in the different 
species are endless in variety. Those which I have 
brought to your notice, in passing through the four sub- 
kingdoms of the animal world, are exceedingly few in 
comparison with all that might be gathered up, and new 
ones are coming to view every day in the researches of 
zoologists. Each species has its peculiar habits, and, of 
course, its corresponding adaptations in its structure. 
The study in this respect has no end, and the fertility of 
the wisdom and skill of the Deity is seen to have no 
bounds. The humblest observer who enters this field 
may find many things that no one has yet recorded, and 
thus may be a contributor to zoological science. 
621. Of the individual adaptations I will notice a few 
of those only which are of a marked exceptional charac- 
ter. The whale is a Mammal having lungs, and yet it 
lives in the water like the fishes. For this it must have 
an especial adaptation in the arrangement of the circu- 
lating system, as described in § 187. So also, as it is a 
warm-blooded animal, its heat must be kept from escap- 
ing too rapidly by a special provision, and this must be 
in consonance with its fish-like habits (§ 186).—The bat 
is a Mammal, and yet, as it is destined to get its liveli- 
hood on the wing and in the dark, it has peculiarly con- 
structed wings for this purpose (§ 58, 59, and 60).—Most 
fishes are shaped with reference to ease and rapidity of 
movement (§ 353). Hence they are like boats for rac- 
ing, long, spindle-shaped ; and they have no projections 
like a shoulder to prevent their gliding swiftly through 
the water. But there are some exceptions, as in the 
short, big-mouthed Lophius (Fig. 172).—Its habits ex- 
plain the reason of the exception. The brain of man is 
but the fortieth or fiftieth part of the weight of his whole 
