THE HONEY DEW. 
39 
of Aphides, 1 may remark that it is very important 
to refer to adult forms for all specific characters, 
and that as a rule, the winged insects are more to 
be relied on than the Apterous. Young individuals, 
particularly those of the broods early in the series, 
often show but partial development of the tail and 
antennge. 
The last-mentioned organs, indeed, mostly want the 
normal number of joints. 
THE HONTEY DEW. 
As no little discussion has arisen with reference to 
the nature and the source of this substance, the fol- 
lowing observations may not be unacceptable. 
This secretion — for all admit it to be such — is plenti- 
fully sprinkled over the upper surfaces of the leaves of 
various trees during the summer. It is more particu- 
larly abundant in the hot weather upon the foliage of 
the lime and sycamore trees, but often the leaves of 
the plum are brought into an almost disgusting condi- 
tion from the glutinous liquid which covers them. 
Honey dew usually appears in the form of shining 
spots which, from their sweet taste, and the fanciful 
idea that it fell from the skies, has received from early 
writers the name of nectar. 
I quote Messrs. Kirby and Spence’s remarks on this 
subject You have doubtless observed what is called 
the honey dew upon the maple and other trees, con- 
cerning which the learned Koman naturalist Pliny 
gravely hesitates whether he shall call it the sweat of 
the heavens, the saliva of the stars, or a liquid pro- 
duced by the purgation of the air. Perhaps you may 
be aware that it is a secretion of Aphides, whose excre- 
ment has the privilege of emulating sugar and honey 
in sweetness and purity.” It issues in liquid drops 
from the abdomen of these insects, not only by the 
