THE THYSANOPTERA, 
121 
Order 7. Thysanoptera. — Thrips and its allies were re- 
ferred by Haliday to a distinct order. The mouth-parts 
form a sort of beak ; the mandibles are bristle- 
like ; the maxillae flat^ triangular^ bearing two- to 
three-jointed palpi; the labial palpi are very 
shorty two- to three -jointed. The wings are small, 
long and narrow, fringed; both pairs of equal 
size, usually without veins. The antenna are 
five- to nine-jointed. 
Order 8. Hem ipt era.— The bugs (Fig. 150) have 
a long beak bent on the breast. They suck the 
Thrips. juices of plants and blood of insects. The chinch- 
bug (Fig. 151) is fearfully destructive in 
certain years to corn and wheat ; collecting 
under the base of the leaves in great num- 
bers, it sucks the sap and kills the plant. 
While most insects live but one and some 
live two years, the seventeen-year Cicada 
(Fig. 152) lives over sixteen years as a larva, 
becoming a pupa and finally acquiring 
wings in the seventeenth year. SquSh-bug' 
The Aphis or plant-louse (Fig. 153) is 
provided with two tubes on the end of the body from which 
Coreus, 
Natural 
Fig. 151.— Chinch-bug. a, 6, eggs; c, e, larva; /, g, pupa; i, beak. 
honey dew'' drops, which attracts ants, wasps, etc. In 
summer the female plant-lice bring forth young alive, and 
as there may be nine or ten generations, one virgin Aphis 
