STATES OF INSECTS. 59 



the complete development of the sexual powers takes 

 place in both sexes, and the animal has arrived at its 

 acme, and can continue its kind a : now the digestive 

 powers diminish in their activity, and love reigns para- 

 mount. When this state is fully attained, no further or 

 higher change is to be expected, and the progress is soon 

 towards decay and the termination of the animal's mortal 

 career. So we see that in fact man and other mammalia, 

 though they do not simultaneously cast their skins like 

 the insect; or pass into a state of intermediate repose, 

 before they attain the perfection of their nature, like the 

 caterpillar ; have their three states, in each of which they 

 acquire new parts, powers, and appetites. 



But a more striking analogy has been traced between 

 the insects that undergo a complete metamorphosis and 

 the vegetable kingdom ; for though the primary analogy 

 seems to be between the Polypus and the Plant, yet the 

 secondary one with the Insect is not by any means remote. 

 There are circumstances to which I shall have occasion 

 hereafter to call your attention, which afford some ground 

 for supposing, that the substance of the insect and the 

 vegetable partakes of the same nature, at least approxi- 

 mates more nearly, than that of the insect and the verte- 

 brate animal ; and every one who has observed these little 

 creatures with any attention, will have observed amongst 

 them forms and organs borrowed as it were from the 

 kingdom of Flora; and vice versa the Botanist, if he 

 makes the comparison, will find amongst his favourite 

 tribes many striking resemblances of certain insects. 

 But the analogy does not stop here ; for the butterfly 

 and the plant appear to have been created with a parti- 



a N. Diet. d'Hisl. Nat. xx. 349—. 



