HOW TO KNOW THE INSEGS 



6a Hind legs fitted for leaping with thick femora. Antennae 

 nine or ten jointed. Front wings often leathery. (The Jump- 

 ing Plant-lice) Fig. 170. Family S, CHERMIDAE 



Fig. 170. Psylla pyrlcola Foerster The Pear 

 Psylla. 



Dark reddish brown, the abdomen banded with 

 black. An enemy of the pear. Len^^th 2-3 mm. 

 (From U.S.D.A.) 



These are tiny Insects that look like minia- 

 ture cicadas. They live on the llm.bs and 

 twigs of plants and may cause severe damage. 

 Some are gall makers. The family Is not a 

 large one. 



Figure 170. 



6b Not as in 6a 7 



7a Legless, wingless, scale or mealy covered insects living 

 and often firmly attached on limbs of plants (females), or 

 without beak, and with but one tarsal joint and one pair of 

 wings and with long antennae (males). The Scale Insects, 

 (Bark Lice, Mealy Bugs, etc.) Fig. 171. Family 10, COCCIDAE 



Fig. 171. Lepldosaphes ulml (L.) The 

 Oyster-Shell Scale, (a, Female with 

 eggs; b, mature female; d, male.) 



Scale dark brovm to black. The young 

 are yellowish, and active for a short 

 time after hatching. One of our most 

 common scales on fruit trees and 

 shrubs. Length; female about 3 mm. 

 Male about 1 mm. 



This Is a fairly large family of 

 highly destructive Insects. The males 

 usually have one pair of wings, and 

 the young run about actively for a 

 short time. Other than this, the 

 usual procedure Is to thrust the suck- 

 ing tube Into the tissue of the plant 

 host, build a waxen scale over the tiny 

 body and spend the entire life In th<=^ 

 Figure 171. One spot. Frult and shade trees ano 



greenhouse and house plants are fre- 



,^ ,, ^ quently heavily damaged. 



7b Not as in 7a 8 



8a Wings opaque, usua 1 1 y whi t i sh, sometimes with colored mark- 

 ings; body and wings covered with white powder; 

 tarsi with two segments. (The White Flies.) 

 Fig. 172. Family 9, ALEYRODIDAE 



Fig. 172. Aleyrodes vaporarlorum Westw. The Green- 

 house White Fly. 



Body and four wings of both sexes covered with 

 white powder. The nymphs resemble the scale In- 

 sects. Provoklngly destructive to house plants and 

 In greenhouses. Length about 1.5 mm.. (From U. S. 



Figure 172„ D. A. ) 



86 



