276 thp: mkchanical functions. 



The mechanical functions of insects scarcely 

 admit of being reduced to general principles, in 

 consequence of the great diversity of forms, of 

 habits and of actions, that is met with among the 

 innumerable host of beings which rank under this 

 widely extended department of the animal creation. 

 In these minute creatures may be discovered all the 

 mechanical instruments and apparatus required for 

 the execution of those varied movements which we 

 witness in the larger animals, and which, though 

 ahnost peculiar to the different classes of those 

 animals, are here frequently united in the same 

 individual. Insects swim, dive, creep, walk, run, 

 leap, or fly with as much facility as fishes, reptiles, 

 quadrupeds, or birds. But besides these, a great 

 number have also movements peculiar to them- 

 selves, and of which we meet with no example in 

 other parts of the animal kingdom. 



In attempting to delineate a sketch of the move- 

 ments of insects, and of the mechanism by which 

 they are performed, I am compelled, by the great 

 extent of the subject, to confine myself to very 

 general views ; and must refer such of my readers 

 as are desirous of fuller information on this subject 

 to the works of professed entomologists. 



The mechanical conditions of an insect in its 

 several states of larva, pupa, and imago, are so 

 widely different, that it will be necessary to con- 

 sider each separately. In many tribes, however, 

 the difference between the larva and the perfect 

 insect is much less considerable than in others. 

 Those belonging to the orders of Hemiptera and 

 Orthoptera, for example, come out of the egg with 

 nearly the same form as that which they have in 



