COLEOPTERA. 



A* Prothorax largely developed, free. 



Normal Coleoptera. 



JB, Prothorax very narrow, collarlike, separated from nieso- 

 tliorax by a suture only. Aberrant Coleoptcra. 



NORMAL COLEOPTEHA. 



A, Mentum emarginate ; outer lobe of maxillae composed 

 of two joints, so as to appear palpiform ; posterior coxae 

 produced backward, on inner side; all tarsi with five 

 joints ; antennae threadlike (except in Gyrinidae, where 

 outer lobe of maxillae is nearly always absent, but the 

 eyes are completely divided, and both intermediate and 

 posterior pairs of legs are broad, flattened, and adapted 

 for s winnning) . A d cp h ag a. 



B. Maxillary palpi elongate, often longer than antennae ; 

 all tarsi with five joints ; antennae with from six to nine 

 joints, clubbed. Paljjicornia. 



C Elytra very short, leaving greater part of abdomen 

 uncovered, with straight suture ; wings completely folded 

 under elytra; abdomen formed of seven or eight seg- 

 ments, all freely moveable; body generally long and 

 narrow ; antennae usually threadlike ; number of tarsal 

 joints variable. Brachelytra. 



U. Antennae nearly always gradually or abruptly clubbed, 

 rarely elbowed, club not composed of plates ; maxillary 

 palpi rarely elongate (or if so, antennae with eleven 

 joints) ; head not produced into a rostrum ; thorax not 

 lioodlike ; femora inserted towards base of trochanters, 

 or if not, anterior coxae conical, and abdomen with six 

 ventral segments (last very small) ; prosternum not pro- 

 duced backward into a spine to fit into cavity of meso- 

 sternum ; body more or less hard ; number of tarsal joints 

 varia])le ; antennae rarely threadlike, in which case the 

 tarsi are five-jointed (at least in female), the outer lobe 

 of maxillae not palpiform, elytra not short and anterior 



