84 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, Lsemophloeus, Brontes) (PL 5, fig. 96.) ............... CUCUJID./E 



Middle coxal cavities closed externally by the sterna ..................... 35 



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



Tribe DIPHYLLINI of the MYCETOPHAGID^B 

 Prosternum prolonged behind, meeting the mesosternum ................. 36 



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



(Atomaria, Crypt6phagus) ......................... CRYPTOPHAGID^ 



Front coxal cavities closed behind (PL 6, fig. 119); larger beetles, usually black, 

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



Group D ACNES of the EROTYLID^B 



37. Hind coxae 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 (PL 6, fig. 119) ....................... 39 



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



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



pubescent beetles. (Bytfcrus.) ............................. BYTURID^ 



Tarsi simple, not lobed; small, coarsely punctured beetles. (Derod6ntus.) 



DERODONTIIXE 



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



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

 Larder-beetle] Attagenus, Anthrenus {Museum-beetle, Carpet-beetle]) (PL 

 5, fig. 94; PL 7, fig. 152) ............................... DERMESTID^E 



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.) 



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

 (PL 7. fig. 131.) .......................................... ANOBIUXE 



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) 

 (PL 5, fig. 103.) ........................................... LYCTIIXE 



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

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

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

 B6strychus, Polycaon [P. confertus, Prune-twig borer], Schistoceros 

 [S. hamatus= Amphicerus bicaudatus, Apple-twig borer]) (APAT1DJ 



BOSTRYCHIDjE 



44. Hind coxae flat or oval, not prominent ................................. 45 



Hind coxae prominent internally, more or less conical .................... 48 



