336 On the Geographical Distribution of Insectx. 



the neighbouring plains, ^th. Living vegetables. These may 

 be considered under two points of view, as insulated indivi- 

 duals, or as assembled into forests, &c. Every part of a plant 

 is liable to be attacked by particular insects, to which it serves 

 as a station. We ought, consequently, to distinguish the roots, 

 the stalk, the leaves, &c. Some authors call the insects 

 which live in the interior of plants, endophytous, while those 

 found on their exterior, whether they live at the expense of 

 the plant or not, are named epiphytous. 



Considered in their collected state, vegetables present dif- 

 ferences no less considerable. Certain insects seem to delight 

 only in extensive forests ; others prefer coppices, gardens, 

 meadows, &;c. Each species is attracted to these different 

 places, not only by the plants which serve it for food, but by 

 certain conditions of heat, light, or humidity. Under the 

 tropics, it is not in general in the depth of the virgin forests 

 that the greatest number of insects is to be found. The per- 

 petual shade which prevails there, induces a degree of coolness 

 and moisture not congenial to most of these animals. They 

 prefer the skirts of woods, or the clearings which appear among 

 them at rare intervals. 



9M, Dead or decomposed vegetables. A multitude of diffe- 

 rent kinds live in these, particularly in their early states. 

 10^/i, Living animals. Mamraiferae and birds are the only 

 subjects, among the vertebrata, liable to be attacked by insect 

 parasites. In the class MoUusca, the Helex nemoralis may be 

 mentioned as being in a like predicament, for it is preyed on 

 by the larva of Drilus flavescens. The rest of the animal 

 kingdom has no relation with the insect tribes. Such of them 

 as live on the vertebrata, are termed epizoites. Wth, Dead 

 animals. The Coleoptera and Diptera are the only orders 

 which make these their pabulum. \2th, Animal rejections. 

 The rejectments of carnivorous animals are frequented by few 

 insects ; but those of herbivorous ones afford a station and 

 nutriment to an entire family of Coleoptera, viz. the Copro- 

 phaga, and also to many other species of all the orders. 



All these stations are subordinate, as far as relates to the 

 perfect insects, to the period of the year at which the latter 

 make their appearance ; for, at all other times, they present 



