ROSE LOUSE. 
331 
domen, as is usual in other insects. On placing a 
piece of writing-paper under a mass of these in- 
sects, it soon became thickly spotted : holding it a 
longer time, the spots united from the addition of 
others, and the whole surface assumed a glossy ap- 
pearance. I tasted this substance, and found it as 
sweet as sugar. I had the less hesitation in doing 
this, having observed that wasps, ants, flies, and in- 
sects without number, devoured it as quickly as it 
was produced. 
“ In the height of summer, when the weather is 
hot and dry, and aphides are most abundant, the 
foliage of trees and plants (more especially in some 
years than others) is found covered with, and ren- 
dered glossy by, a sweet clammy substance, known 
to persons resident in the country by the name of 
honey-dew : they regard it as a sweet substance fall- 
ing from the atmosphere, as its name implies. The 
sweetness of this excrementitious substance, the 
glossy appearance it gave to the leaves it fell upon, 
and the swarms of insects this matter attracted, 
first led me to imagine that the honey-dew of plants 
was no other than this secretion, which further ob- 
servation has since fully confirmed. Others have 
considered it as an exsudation from the plant it- 
self. Of the former opinion we find the Rev. 
Mr. White, one of the latest writers on natural 
history that has noticed this subject. But that it 
neither falls from the atmosphere, nor issues from 
the plant itself is easily demonstrated. If it fell 
from the atmosphere it would cover every thing in- 
