LIBRARY

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CLASSIFICATION OF INSECTS
37. Mouth parts arising from the underside of the base of the head near
the fore COXal, enclosed in a jointed rostrum for sucking. (HOMOP­
TERA: Cicadas, Leafhoppers, Aphids, Scales, etc.) . HEMIPTERA
Mouth parts normally situated at the front of the head . 38
38. Wings net-veined, with many longitudinal and cross veins 39
Wings not net-veined, with branching and few cross vein!\ 40
39. Tarsi with less than five segments 40
Tarsi five-segmented. rarely less . 44
40. Antenna! inconspicuous, small, short, setiform . 41
Antenna! conspicuous and of many forms . '" 42
41. Fore and hind wings nearly equal in size; tarsi three-segmented. (Damsc\fiies,
Dragonflies.) . . ODONATA
Fore wings much larger than the hind wings; tarsi four-segmented.
(Mayflies.) . . EPHEMERIDA
42. Tarsi two- or three-segmented 43
Tarsi three-segmented; fore tarsi enlarged; males only winged. (Embiids.)
. . EMBIOPTERA
Tarsi [our-segmented; wings nearly equal. (Termites.) . ISOPTERA
43. Fore wings equal to or narrower than the hind wings. (Stoneflies.)
PLECOPTERA
Fore wings larger than the hind wings. (Psocids.). . CORRODENTIA
44. Abdomen with long, filiform, many-segmented caudal filaments. (Certain
Mayflies.) . . EPHEMERIDA
Abdomen without long many-segmented caudal filaments 45
45. Head prolonged into a beak. (Scorpionflies.) . . MECOPTERA
Head not prolonged into a beak . . 46
46. Prothorax quadrate or nearly so; hind wings plicated or the anal area
folded fan-like in repose; aquatic species . . 47
Prothorax cylindrical or subcylindrical; hind wings Inay be rarely
folded fan-like in repose; mostly terrestrial.species (TRICHOP­
TERA have hind wings folded and are aquatic.) 48
47. Cerci long and slender, many-segmented; wings folded flat and closely
over the body in repose. (Stoneflies.) . PLECOPTERA
Cerci absent.; wings folded loosely or roof-like over the body in repose.
(Dobsonflies, Fishflies, Sialids.) MEGALOPTERA
48. Pro thorax very long and slender; wings subequal. (Serpentfiies.)
RAPHIDIODEA
Prothorax not greatly lengthened; wings dissimilar 49
49. Tarsi two- or three-segmented 50
Tarsi four- or five-segmented . 51
50. Cerci present; body less than 3 mm. in length. (Zorapterans.) ZORAPTERA
Cerci absent; body 3 mm. long or longer. (Psocids.) . CORRODENTIA
51. Abdomen with long many-segmented caudal filaments. (Certain
Mayflies.) . . EPBEMERIDA
Abdomen without long caudal filaments. 52
52. Prothorax heavily sclerotized or horny; fore wings larger than hind
wings, the latter with but few simple veins; mandibles well developed;
palpi short. (Sawflies, Homtails, Gallflies, Ants, Wasps,
Bees.) . . HYMENOPTERA
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p.263
p.228
p.211
p.177
p. 159
p. 148
p. 184
p.211
p. 399
p.148
p.366
p.394
p.174
p. 184
p.211
p.SIt)