LARVAL FORMS OF COLFOPTERA 



5. Tentorial cross-arm internal. (Palpiger large, bearing lacinia 

 and palpns; epipleiirum protuberant on all abdominal seg- 

 ments; legs present) Lepturinae (pis. 99 G, H, 100 



H-L) 

 Tentorial cross-arm (tb pi. 100 M) in the same plane as the 

 hvpostoma. bridging the ventral surface of the head. (Larva 

 very elongate and slender; legs present) 



Disteniinae (pi. 100 M) 



R. BOSTRICHOIDEA 



Key to Families 



1. Head protracted; mandible dentate. (Terga hairy or not. 



often with rows or patches of asperities) 2 



Head retracted ; mandible not dentate, usually with gouge- 

 shaped distal end. (Terga without asperities) 3 



2. Thoracic spiracle pushed forward to anterior margin of pro- 



thorax. (Spiracles bearing a single spoutlike prolongation 

 (prl pi. 101 E) ; a small, often curved, transverse sclerome 

 present at the end of a median groove between the longitudi- 

 nallv placed anal lobes (ats pi. 101 Ct) ; terga without as- 

 perities) Ptinidae (pi. 101 A, B, E) 



Thoracic spiracle not reaching anterior margin of prothorax. 

 (Spiracles without single spoutlike prolongations, except in 

 Anohium, where they are large; with or without a small, 

 transverse sclerome at the end of a longitudinal, median 

 anal groove ; straight, curved, or hook-shaped tergal asperi- 

 ties on all or some of the segments, except in Ozognafhus 



and Lasioderma) Anohiidae (pi. 101 C, D, F-N, 



X, Ae, Oe) 



3. Mandible without a dorsal, molarlike process ; epipharynx 



without a large sclerome; lacinia mandibulae absent 



BostricJiidae" (pi. 101 0-W, 



Y, Z) 



Mandible with a dorsal, molarlike process, grinding against a 



large sclerome in epipharynx; lacinia mandibulae present 



and fleshy -1 



4. Abdominal spiracles subequal in size 



Psoidae'' (pi. 102 A-E) 



" The family includes all the genera usually placed in the 

 family Bostrichidae, except the genera which are here tabulated in 

 the familj' Psoidae. 



" The family Psoidae includes tlie foHowing genera, usually 

 placed in the Bostrichidae : Stephanopdchjis (Saalas, IT., Die 

 Fichtenkafer Finlaiuls, part 2, 1923. pp. 179 and 700, figs. 115- 

 120), Rhizopertha, Dinoderus, and Dinoderopsis (Lesne, P., Les 

 coleopteres Bostrychides de I'Afrique tropical francaise, Paris, 

 1924, pp. 47 and 77), Pohicaon, and P.sor/. 



62 



