LIBRARY

CLASSIFICATION OF INSECTS 55
10. Abdomen constricted at the base; cerci absent. (Ants, Wasps, and
many parasitic forms.) . . . . HYMENOPTERA p.619
Abdomen not constricted at the base; cerci present . . . . 11
11. Tarsi two-segmented; cerci unsegmented. (Zorapterans.). ZORAPTERA p.174
Tarsi three-segmented, basal segment of fore tarsus swollen. (Embiids.)
. . EMBIOPTERA p.177
Tarsi two- to five-segmented . . 12
12. Hind legs enlarged for jumping. (Grasshoppers, Katydids, Crickets.)
ORTHOPTERA p. 87
Hind legs normal, not specialized for jumping . 13
13. Prothorax conspicuously lengthened; forelegs raptorial. (Mantids.)
MANTODEA p. 124
Prothorax not greatly lengthened; forelegs normal. 14
14. Cerci absent; body well armored; antennre usually ll-segmented.
(Beetles, Wccvihi.) . . COLEOPTERA p. 518
15. Cerci usually unsegmented 16
Cerci usually segmented . 17
16. Cerci short, corneous, and forceps-like; not ectoparasitic on mammals;
widely distributed species. (Earwigs.) DERMAPTERA p. 131
Cerci relatively long and slender; cctoparasitic on rodents; rare South
African species. (Hemimerids.) DIPLOGLOSSATA p. 145
17_ Cerci three- or more segmented . 18
Cerci one- to three-segmented or more 19
18. Body flattened and oval: hypognathous, i.e" head vertical and mouth
parts directed downwards; prothorax normal. (Cockroaches.)
BLATTARlA p. 109
Body somewhat cylindrical; prognathous, i.e., head horizontal and
mouth parts directed forwards; prothorax quadrate. (Grylloblattids.)
. GRYLLOBLATTODEA p. 105
19. Tarsi five-segmented; body long and stick-like or broad and flat or leaflike.
(Walkingsticks, Leaf Insects.) . PHASMIDA p. 116
Tarsi two- to four-segmented; body neither stick-like nor leaf-like 20
20. Tarsi apparently four-segmented; cerci two- to six-segmented; antenrue
usually more than nine-segmented. (Termites.). . ISOPTERA p. 159
Tarsi two-segmented; cerci unsegmented; antennre nine-segmented;
minute, rare species. (Grylloblattids.) GRYLLOBLATTODEA p. 105
21. Ectoparasites on birds and mammals 22
Not ectoparasites on birds and mammals; largely phytophagous 24
22. Body strongly compressed laterally; rarely with vestigial wings; small
jumping or burrowing insects. (Fleas.) . . SIPHONAPTERA p. 819
Body not compressed laterally; crawling insects 23
23. Antennre inserted in pits and not visible from above. (Louse Flies:
PUPIP ARA.) . DIPTERA p. 728
Antennre exserted and plainly visible from above. (Sucking Lice.)
ANOPLURA p. 202
24. Apical segment of tarsus terminating in a bladder-like organ and without
well-developed claws. (Thrips.) . . THYSANOPTERA p.247
Apical segment of tarsus not bladder-like and terminating in welldeveloped
claws (HOMOPTERA). . HEMIPTERA p. 263