579 
parent wings. The majority of plant lice are aerial in their habits, 
but some varieties also assume a subterranean form, and these are 
among the most destructive and widespread, the phylloxera and 
woolly aphis being the best known. 
Their methods of reproduction are most unique and peculiar 
to themselves, and the different forms they assume—some winged 
and others wingless, some laying eggs, others bringing forth young 
alive and often without the intervention of the male, which in some 
forms has never been recognised, and make them at once interesting 
and puzzling to the naturalist and entomologist. 
In many varieties a sweet substance is produced, called “honey- 
dew,”’ which is exuded through two tubes situated on the back near 
the posterior part of the insect (see page 583), which can readily be 
seen with the naked eye. This is the substance, when produced 
in large quantities, that drips upon the leaves and branches of 
infected plants. This honeydew is devoured by bees, wasps, and 
ants, and supplies food to the black soot fungus or fumagine. It 
is commonly believed that ants destroy plant lice, but the contrary 
is the fact. Ants treat and regard plant lice as milch cows. Ants 
have been observed to approach a plant louse, place its antenne 
on its back, stroking it gently, when the louse will give forth its 
honeydew, which the ant will immediately drink up. The ants 
take good care of the lice, and will transport them to new pastures 
when old ones fail, thus aiding greatly in their distribution. 
Plant lice obtain their sustenance by sucking the juices of 
plants, by inserting their proboscis in woody plants, in the tender 
terminal growths, peduncles of roses, etc., and in the succulent parts 
of plants and roots. While the amount taken by an individual is 
almost infinitesimal, their immense numbers often cause most 
serious injury to the plant they infest, and sometimes its destruc- 
tion. 
Caspace ApHIs (Aphis brassice, Linn.). 
There are several modes of dealing with this pest, and among 
them the best is to spray with Nos. 7, 8, 10, 14, 15, 19, or 20. 
(See pp. 527-531). 
Aphis-feeding Ladybird (Coccinella sep- 
tempunctata), a adult beetle; 6, larva; 
c, pupa. All enlarged (after Berlese). 
Two species of ladybirds—Leis conformis and Coccinella septem- 
punctata—which prey upon this aphis have been introduced into 
the State, as well as two species of Ichneumon flies. 
