390 FOOD OF INSECTS. 



testines which are filled with it. This supposition, which 

 if correct renders invalid the definition by which Mirbel 

 (and my friend Dr. Alderson of Hull long before him) 

 proposed to distinguish the animal and vegetable king- 

 doms, is certainly not inadmissible ; for, though we might 

 not be inclined to give much weight to Father Paulian's 

 history of a flint-eater who digested flints and stone a , the 

 testimony of Humboldt seems to prove that the human 

 race is capable of drawing nutriment from earth, which, 

 if the odious Ottomaques can digest and assimilate, may 

 doubtless afford support to the larvae of Ephemeras. Yet 

 after all it is perhaps more probable that these insects 

 feed on the decaying vegetable matter intermixed with 

 the earth in which they reside, from which after being 

 swallowed it is extracted by the action of the stomach : 

 like the sand that, from being found in a similar situ- 

 ation, Borelli erroneously supposed to be the food of 

 many Testacea, though in fact a mere extraneous sub- 

 stance. 



The majority of insects, either imbibing their food in 

 a liquid state, or feeding on succulent substances, require 

 no aqueous fluid for diluting it. Water, however, is es- 

 sential to bees, ants, and some other tribes, which drink 

 it with avidity ; as well as in warm climates to many Le- 

 jridoptera, which are there chiefly taken in court yards, 

 near the margins of drains, &c. Even some larvae which 

 feed upon juicy leaves have been observed to swallow 

 drops of dew ; and one of them {Bombyx potatoria\ which 

 (according to Goedart) after drinking lifts up its head 

 like a hen, has received its name from this circumstance. 

 That it is not the mere want of succulency in the food 

 * Diction itaire Physique, 



