HETEROMEBA. 8 



ii. Tarsal claws pectinate CISTBLID.E. 



(Alleculida.) 



II. Anterior coxal cavities open behind. 

 i. Anterior coxae globose or ovate. 



1. Head not suddenly constricted behind eyes. 



A. Thorax subovate, orcordiform, narrowed in front and 

 usually narrowed behind, often narrower at base than 



apex, and narrower at base than base of elytra . . . PYTHID.B. 



B. Thorax not narrower at base than at apex, and not, 



or scarcely, narrower at base than base of elytra . . MELAXDBYIDJ:. 



2. Head suddenly constricted behind eyes; thorax not 



narrower at base than elytra. 



A. Posterior tibiaa as long as the tarsi ; tarsal claws with 

 a rudimentary tooth at base; penultimate joint of tarsi 



strongly bilobed SCBAPTIIDS. 



B. Posterior tibia; much shorter than the tarsi ; tarsal 

 claws usually plainly toothed; penultimate joint of 



tarsi simple MOBDELLIDJE. 



ii. Anterior coxa? long, prominent and conical. 



1. Head strongly and suddenly constricted behind. 



A. Thorax at base not narrower than base of elytra . . RHiPiDOPHORru.E. 



B. Thorax at base plainly narrower than base of elytra. 



a. Tarsal claws split from base to apex MKLOIDJB. 



b. Tarsal claws not split. 



a*. Autennae long, serrate or pectinate ; head ex- 



serted, horizontal ; siae large PIBOCHHOID*. 



b*. Antennse moderate or long, filiform (in our 



species) ; head deflexed ; size very small, 

 af. Penultimate joint of the tarsi minute, hidden 

 within the lobes of the preceding joint, which is 

 strongly bilobed ; head constricted immediately 



behind the eyes, which are large XTXOPHir.iD.E. 



bf. Penultimate joint of tarsi not minute, bilobed ; 

 head constricted at some distance behind the 

 eyes, which are moderate or small ANTHICTD.E. 



2. Head not strongly and suddenly constricted into a neck 



behind (EDEHEBID.E. 



TENEBRIONIDJE. 



This important family contains a very large number of genera and 

 species, which are distributed over the whole surface of the globe ; in 

 the Munich catalogue, published in 1870, four thousand five hundred 

 species are enumerated, but this number has been largely increased since 

 that time, and is perpetually being added to ; although their distribution 

 is almost universal, yet in some large districts it appears to be very 

 uneven, more especially in North America, where they form the 

 characteristic feature of the Coleopterous fauna in California, but in the 

 eastern portions of the continent are scarce ; in Europe the family is 

 represented by about one hundred and twenty five genera, and several 

 hundred species, but in Britain only about thirty species, representing, 

 however, some nineteen genera, have hitherto been discovered ; these 

 may be subdivided and classified under the tribes below mentioned, but 

 it is obvious that with our very limited fauna any classification is un- 



B 2 



