290 NEW YORK STATE MUSEUM 



hb Mandibles suctorial, without teeth at middle or at base 



c Apex of the abdomen not armed with four hooks. . .D y t i s c i d a o 



cc Apex of the abdomen armed with four hoolis G y r i u i d a e 



•aa Tarsi never with more than a single claw; in some species the lo,;;s 

 entirely wanting 

 b Cerci present as jointed appendages, in some cases hardly more than 

 a jointed tubercle 

 c Larvae long, wirewormlilie; the caudal end of the abdomen strongly 



chitinized; larvae terrestrial Elate ridae 



cc Larvae soft bodied, not wirewormlike; the caudal end of the abdo- 

 men not more strongly chitinized than the remainder of the body 

 d Eyes in groups of five or six 



e Larvae terrestrial, feeding in fungi S c a p h i d i i d a e 



ee Larvae aquatic 



f Eyes in groups of five H a 1 i p 1 i d a e 



ff Eyes in groups of six Hydrophilidae 



dd Eyes in groups of four, two, or none; larvae terrestrial 



e Labrum present, distinct; body frequently lepismoid in form 



S i 1 p h i d a e 

 ee Labrum wanting; body not lepismoid in form, the sides sub- 

 parallel 

 f Eyes present, usually in groups of four. .Staphylinidae 



ff Eyes wanting H i s t e r i d a e 



M Cerci wanting 



c Larvae without thoracic legs 



d Head broader than the remainder of the body; the body 

 depressed; larvae wood borers 

 e Maxillary palpi with three or four segments; the labial palpi 

 with three segments; eyes frequently present 



Cerambycidae 

 ee Maxillary palpi with two segments; the labial palpi minute, 



unsegmented; eyes usually wanting Buprestidae 



dd Head not broader than if as broad as the remainder of the body; 

 the body cylindrical; the larvae infesting seeds.. B r u c h i d a e 

 cc Larvae with distinct thoracic legs 



d Larvae scarabaeoid, that is, white grub-like, in form 

 e Eyes present 



/ Eyes six in number;, larvae case-bearers 



Chrysomelidae 

 ff Eyes two in number; larvae not case-bearers T r o x 



Scarab aeidae 

 ee Eyes wanting, or if present, usually of not more than a single 

 ocellus 

 f Antennae three jointed, minute, hardly projecting beyond the 



side of the head; larvae usually small Ptinidae 



ff Antennae two to six jointed, never minute, usually as long 

 as, or longer than, the mandibles; larvae usually large 



L u c a n i d a e 

 Scarabaeidae 

 ■dd Larvae not scarabaeoid in form 



e Apex of the abdomen not more strongly chitinized than the 

 remainder nor produced into one or two prominent projec- 

 tions 



