LARVAL FORMS OF COLEOPTERA 



Disteniinae might possibly with equal .justification be placed in 

 either of the two series, the Bostrichoidea or the Chrysomeloidea, 

 both closely associated with the Cerambycoidea, rather than in the 

 latter series. The larva of the Disteniinae differs from all other 

 cerambycoid larvae in the development of the ventral structures 

 of the head and chiefly in the lack of a distinct gula, but the 

 presence of a short gula lying on top of the median part of a broad, 

 well-defined hypostomal bridge and fused with it is just the essen- 

 tial character by w^hich the larvae of the Cerambycoidea can be 

 separated from the ones of the Bostrichoidea and Chrysomeloidea.'^ 



Key to Subfamilies 



1. Head oblong, sides parallel or converging behind. (Epistoma 



never projecting; tentorial cross-arm internal; epipleurum 

 protuberant on several or all abdominal segments ; legs 



usually absent) Lamiinae (pis. 99 I, J, 100 A) 



Head transverse, wider behind the middle 2 



2. Epistoma projecting over clypeus, except in Parandra; frons 



projecting over epistoma, dentate or carinate, except in 

 Parandra. (Tentorial cross-arm in the same plane as the 



hypostoma and forming a bridge behind it ; legs present ) 



Prioninae''' (pis. 99 A, B, 100 

 B-F) 

 Neither epistoma nor frons projecting 3 



3. Mandible with oblique, straight cutting edge, except in 



Opshnus 4 



Mandible with rounded, gougelike cutting edge (pi. 100 G). 

 (Tentorial cross-arm in the same plane as In'postoma and 

 forming a bridge behind it ; clypeus filling space between 

 dorsal articulations of mandibles ; epipleurum protuberant 

 only on last three abdominal segments; legs present or 



absent) Ceramhijciiuie (pis. 99 E, F, 



100 G) 



4. Dorsal margins of epicranial halves j)artly fused behind frons. 



(Tentorial cross-arm internal; legs present) 



Aseminae (pi. 99 C, D) 

 Dorsal margins of epicranial halves separated behind frons .5 

 ^^ Craighead, F. C, North American Cerambycid Larvae, 

 Canada Dept. Agr., Bui. 27, New Series, Technical, Ottawa, 1923, 

 pp. 6, 26, and 99-101 with figures. 



'" Craighead, F. C, Larvae of Prioninae, U. S. Dept. Agr., 

 Off. Sec, Report 107. 1915, pp. 1-24, eight plates. 



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