LARVAL FORMS OF COLEOPTERA 



Anchijf(i):sus with, and in Ptilodactyla without, gills from 

 tenth abdominal segment) Ptilodacfi/lidae^^ (pis. 67 A-J, 



68 xV-H, 69 A-H) 

 Antenna short ; tenth abdominal segment without diverticles. 

 (Gills lacking) Eurypogonidae^'^ (pi. 69 I-S) 



4. Lateral expansions of eighth abdominal segment present 



Psephenidae - Euhricmacinae^'^ 



(pi. 70 A-E, G) 



Lateral expansions of eighth abdominal segment absent 



(Mandible dimorphic in the same species, either simple, 



rather short, and terminally truncate, or composed of a 



basal and a terminal, pointed portion) 



Psephenidae - Pseplieyiinae (pi. 

 70 F, H-P) 



5. Nine pairs of spiracles present, all projecting and either cribri- 



form, or biforous but of a deviating sinuous type. (One 

 ocellus on each side ; ninth abdominal segment conical, or 

 subconical and terminally bifurcate ; appendix from oper- 

 culum short and broad) Chelonariidae^^ (pi. 71 A-J) 



Spiracles present in a number varying from one to nine pairs, 

 either annuliform or regularly biforous, never sinuous 6 



6. Five ocelli on each side. (Bodj^ subcylindrical ; mandible 



apically bidentate ; ninth abdominal tergite terminally emar- 



ginate) Dn/opidae-Larinae {Lara) (pi. 



72 A-I) 

 One large ocellus on each side 7 



7. Head concealed beneath prothoracic dorsal shield; ninth ab- 



dominal segment dorsally flattened, more or less semicircular, 

 or subrectangular. (^Mandibles either simple and terminally 

 obtuse, or terminally tridentate, or composed of a basal and 

 a terminal pointed portion) 



Dryopidae-Pelonominae (Pelon- 

 ornus, Helichus, and Psepli- 

 enoides) (pis. 70 Q-V, 72 

 J-K, 73 F-0) 

 Head exserted and visible from above ; ninth abdominal seg- 

 ment subconical, often distally furcate. (Mandibles termi- 

 ^^ According to the characters of the imagines, the Ptilodacty- 

 lidae, including Anchytarsus and Ptilodactyla, and the Eurypo- 

 gonidae, including Eurypogon, are usually placed in the series 

 Dascilloidea. 



^' The subfamily Eubrianacinae, based on the genus Euhrianax, 

 is usually placed in the Dascilloidea. 



•''- The family Chelonariidae is usually placed in the series Dascil- 

 loidea. 



45 



