122 ECONOMIC ENTOMOLOGY 



Wheat or Strawberry Thrips {Euthrips tritici Fitch). — The most 

 common thrips and found on many cultivated plants. Injurious to 

 strawberry, apple, peach and wheat. Several generations in a season 

 (Fig. 76). 



Adult. — Small, ^'20 inch long, brownish yellow. 



Eggs. — Small, whitish, curved oblong; laid singly in lower part of 

 calyx and in flower stalk of strawberry; hatch in 3 days. 



Nymphs. — Three moults; mature in 9 or 10 days. 



This thrips produces "button" strawberries. 



Control. — Spray with nicotine or kerosene emulsion. 



ORDER HOMOPTERAi 

 Chief Economic Families 



A. Tarsi i or 2-jointed; antennae usually prominent; beak apparently arising 

 from sternum. — Group Slernorhynchi. 

 B. Tarsi i-jointed; adult male with beak and 2-winged; female wingless 

 with body scale-like, or gall-like, or grub-like, and covered with waxy 

 secretion. — Coccidce (Scale Insects), p. 123. 

 BB. Tarsi 2-jointed; wings usually 4. 



C. Wings white, opaque. — Alcyrodidce (White-flies), p. 151. 

 CC. Wings transparent. 



D. Legs long and slender; antennae 3-7-jointed. — Aphldida 

 (Plant-lice), p. 136. 

 DD. Hind legs fitted for leaping; antennae 9 or lo-jointed. — 

 Psyllida (Jumping Plant-lice), p. 152. 

 A A. Tarsi 3-jointed, antennae minute; beak evidently arising from mentum. — 

 Group Auchenorhynchi. 



B. Ocelli 3; males with musical organs. — Cicadidcc (Cicadas), p. 156. 

 BB. Ocelli 2 or wanting; males without musical organs. 



C. Antennae inserted on side of cheek beneath the eyes. — Fulgorida. 

 CC. Antennae inserted in front of and between the eyes. 



D. Prothorax prolonged into a horn above the abdomen. — 

 MembracidcB (Tree Hoppers), p. 157. 

 DD. Prothorax not prolonged above the abdomen. 



E. Hind tibiae armed with two stout teeth and tip crowned 

 with short stout spines. — Cercopida (Spittle Insects), 



P- 153. 

 EE. Hind tibias with a double row of spines below. — 

 CicadellidcB or the Jassoidea{L&?ii Hoppers), p. 154. 



' The old order Hcmiplera is here broken up into three orders viz.: Homoptera, 

 Hemipiera and Siphunculata (see p. 94). 



