HALF- WINGED INSECTS 
331 
The True Frog-hoppers are small insects about a quarter of 
an inch long, found among grass and bushes. The fore wings are 
of rather a stout consistency and uniform in colour (often yellowish), 
and the hind wings transparent. The larvae are soft grubs, and 
live in the masses of froth so common in grass and bushes, which are 
vulgarly known as “ cuckoo-spit.” 
Passing over several families of small species, we arrive at two 
which contain many very destructive insects. The Aphides, Plant- 
LiCE, or Smother-flies are the small green or brown winged or 
wingless insects which frequently cover the shoots of roses and 
other trees and plants, and exude a sweet sticky substance, called 
“ honey-dew,” very attractive to ants. One species, known as the 
American Blight, is extremely destructive to apple-trees, patches 
of a substance resembling white cotton appearing on the bark. 
Under these patches the bark rots from the attacks of the insects, 
the pest being very difficult to eradicate. 
Many of the Aphides exhibit the curious phenomenon known 
as “ alternation of generations.” The first 
brood consists of winged males and females ; 
but the eggs which the latter lay produce 
exclusively wingless females, or rather sexless 
creatures capable of laying eggs, and these 
multiply indefinitely for a time, till perfect 
males and females are again reproduced. In 
some cases the winged forms live on the 
leaves of trees, and the wingless forms at 
the roots of grass, etc. One of the most 
destructive of all these insects is the VlNE- 
APHIS, which was probably introduced into 
Europe from America, and which threatened 
at one time almost to destroy the vine in- 
dustry in France. Wingless sexless forms 
live and multiply at the roots of vines ; and 
U' 
1 
L, 
photo by P. DandCf F.Z.S. 
APHIS 
sexual %vitigless form 
in summer winged males and females are 
produced, which fly up, and lay eggs on the 
leaves ; while some of the wingless insects 
also quit the ground, and form small galls on the vine-leaves. 
Although very abundant in America, the insect is not nearly so 
destructive to the plants which it attacks as in Europe. 
Some species of SCALE-INSECTS are almost equally destructive, 
especially to greenhouse plants. The male is slender and two- 
winged, but the female is wingless and often legless, and after de- 
positing her eggs usually dies above them, thus forming a covering 
to protect them from injury. Cochineal consists of the bodies of a 
species of scale-insect which infests the leaves of a cactus in Mexico. 
The True Lice are found on various species of mammals, 
and imbibe their food through a proboscis. The BlRD-LICE, or 
Biting-lice, form a well-defined group by themselves. They are 
sometimes regarded as forming distinct orders of insects ; but 
some authors treat the first group as a degraded family of insects 
allied to the Frog-hoppers, and the second group as an equally 
degraded and aberrant family allied to the Lace-winged Insects. 
1 
Photo by W. P. Dando, F.Z.S. 
SCALE-INSECT 
The females die.^ co’vering their eggs 
•with their ewn bodies 
SCALE-INSECTS 
Sho'wing their appearance •zvhen 
cro’wded together on a branch 
