44 ILLINOIS BIOLOGICAL MONOGRAPHS (362 



16(17) Legs with tibia minute, distinctly shorter and smaller than femur; maxillae with 

 stipes without cephalo-ventral triangular projection; mandibles with two setae; 



labrum without a median longitudinal depression 17. 



SELANDRIINAE (in part). 



17(16) Legs with tibia large, usually subequal to or longer than femur; maxillae with stipes 

 with cephalo-ventral triangular projection; mandibles with 1, 2, or 3-4 setae; labrum 

 with or without a median longitudinal depression TENTHREDININAE. 



18(13) Antennae not conical, with one segment; labrum with secondary longitudinal 

 sutures; small but distinct crescentic glandubae dorsad of spiracles. CIMBICINAE. 



19(12) Third abdominal segment with five, rarely three or four, annulets on dorsum; 

 body with conspicuous branched spines or tubercles. BLENNOCAMPINAE (in part) . 



20(3) Thoracic legs with four segments, modified 21. 



21(22) Tenth urotergum and prothoracic and mesothoracic tergites with conspicuous fleshy 

 pointed protuberances; body not tadpole-like EMPHYTINAE (in part). 



22(21) Tenth urotergum and prothoracic and mesothoracic tergites without conspicuous 

 fleshy pointed protuberances; body often distinctly tadpole-like. 



PHYLLOTOMINAE (in part). 



23(2) Larvapods on abdominal segments 2-7 and 10, rarely on segments 2-7 or 2-6 and 

 10 24. 



24(39) Thoracic legs with five segments, normal in form; larvapods on segments 2-7 and 

 either with or without anal larvapods 25. 



25(36) Larvapods present on the ultimate segment, either normal and separated or fused 

 on the meson, forming a single prominence 26. 



26(35) Anal larvapods normal and separated 27. 



27(28) Antennae with five segments; third abdominal segment with six annulets; tenth 

 abdominal tergum with several caudal protuberances. HOPLOCAMPINAE (in part). 



28(27) Antennae with four, rarely three, segments; third abdominal segment usually 

 with less than six annulets; tenth abdominal tergum with or without caudal protu- 

 berances 29. 



29(32) Abdominal segments 1-7 on ventro-meson with an eversible gland; body often with 

 numerous conspicuous setae, setae arising from distinct tubercles; antennae with four 

 segments 30. 



30(31) Body with numerous conspicuous multisetiferous tubercles, each tubercle bearing 

 several long setae, some of which are distinctly longer than others; third abdominal 

 segment with four annulets, annulet 1 with a transverse row of setae, annulets 2 and 

 3 with a transverse row of setiferous tubercles; tenth abdominal tergum never with 

 caudal protuberances altho with numerous long setae; setae barbed . CLADIINAE. 



31(30) Body without numerous conspicuous multisetiferous tubercles, if tubercles present, 

 they do not bear several long setae some of which are distinctly longer than others; 

 third abdominal segment with varying number of annulets; tenth abdominal tergum 

 sometimes with caudal protuberances; setae not barbed NEMATINAE. 



32(29) Abdominal segments 1-7 on ventro-meson without an eversible gland; body never 

 conspicuously setiferous; antennae with three or four segments; third abdominal 

 segment with three or five annulets 33. 



33(34) Antennae with four segments; third abdominal segment with five annulets; abdom- 

 inal segments 2-4 and 8 or 2-5 and 8 without a postsubspiracular sucker-like pro- 

 tuberance HOPLOCAMPINAE (in part). 



34(33) Antennae with one segment ; third abd ominal segment with three annulets ; abdominal 

 segments 2-4 and 8 or 2-5 and 8 each with a postsubspiracular sucker-like protuber- 

 ance ACORDULECERINAE. 



