y 



34 Key to Families of North American Insects. 



34. Middle coxal cavities open externally, i. e. not closed by the meeting of the 



meso- and metasterna; body elongate, greatly flattened. (Silvanus, Cftcu- 



jus, Laemophloeus, Brontes) (PI. 5, fig. 96.) CUCUJIDiE 



Middle coxal cavities closed externally by the sterna 35 



35. Prosternum not prolonged. (See couplet 74.) 



Tribe Diphyllini of the MYCETOPHAGID.aE 

 Prosternum prolonged behind, meeting the mesosternum 36 



36. Front coxal cavities open behind (PI. 6, fig. 114); small or minute species. 



(Atomaria, Cryptophagus) CRYPTOPHAGID.ffi 



Front coxal cavities closed behind (PI. G, fig. 119); larger beetles, usually black, 

 with orange-red spots. (Megalodachne) (PI. 7, fig. 168). 



Group DXcnes of the EROTYLIDiE 



37. Hind coxge dilated into plates which are grooved for the reception of the 



femora 38 



Hind coxae not thus dilated, nor grooved for the reception of the femora .... 42 



38. Front coxal cavities closed behind (PI. 6, fig. 119) 3» 



Front coxal cavities open behind (PI. 6, fig. 114) 40 



39. Second and third joints of tarsi lobed beneath; plate of hind coxae feeble; small, 



pubescent beetles. (Byturus.) BYTURIDiE 



Tarsi simple, not lobed; small, coarsely punctured beetles. (Derodontus.) 



DERODONTID-^ 



40. Antennae with the last three joints much enlarged, forming a strong club; 



small, or rather small, often scaly beetles. (Dermestes [D. lardarius. 

 Larder-beetle] Attagenus, Anthrenus [Museum-beetle, Carpet-beetle]) (PI. / 



5. fig. 94; PI. 7, fig. 152) DERMESTID.S "^ 



Antennae not capitate 41 



41. Tarsi with a large, hairy pad (onychium) between the claws; moderate-sized 



or large, elongate-oval beetles; tibial spurs present, small. (Sandalus.) 



RHIPICERID.^ 



Onychium not developed or very small; no tibial spurs. (Sitodrepa, Anobia) 



(PI. 7. fig. 131.) ANOBIIDiE 



42. First joint of tarsi very short and indistinctly separated from the second. .43 

 First joint of tarsi distinct, when rarely very short, the first ventral segment 



is not elongated and the head not deflexed 44 



43. First ventral segment elongated, always much longer than the second; antennae 



with a quite distinct two-jointed club; small elongate beetles with prominent 

 head not covered by the prothorax. Powder-post beetles. (Lyctus) 



(PI. 5, fig. 103.) LYCTIDiE 



First ventral segment not elongated; antennal club three- or four-jointed; head 

 usually deflexed and protected by the prothorax; dechvity of elytra often 

 toothed or spined; elongate, more or less cylindrical beetles. (Sinoxylon, 

 Bostrychus, Polycaon [P. conjertus. Prune-twig borer], Schistoceros 

 [S. hamatus= Amphicerus bicauddtus, Apple-twig borer]) {APA TIDJ'^) > 



BOSTRYCHIDiE 



44. Hind coxae flat or oval, not prominent 45 



Hind coxae prominent internally, more or less conical 48 



