396 IXSECTA. 



The remaining Blapsides are ^stributed under various genera, such as 

 Gonopus, Asida, Pedinus, Blaptinus, &c. 



We now come to Melasoma, provided with wings. Their body 

 is usually oval or oblong, depressed or but slightly elevated; their 

 thorax square or trapezoidal, and its posterior extremity as wide as 

 the abdomen. The palpi are larger at the extremity; the last joint 

 of the maxillary palpi has the figure of a reversed triangle, or is se- 

 curiform; the mentum is but slightly extended in width, and leaves 

 the base of the maxillas exposed. 



These Insects compose the third and last tribe of the Melasoma, 

 that of the Tenebkionites, formed of the single genus 



Tenebeio, 

 As originally ari'anged by Fabricius, and to which we will annex his Opa- 

 trum and Orthocera; they will serve for types of as many particular divisions. 



1. Those in which the body is oval; the thorax nearly trapezoidal, arcu- 

 ated laterally, or forming a semioval, truncated anteriorly, wider than the ab- 

 domen, at least at its posterior margin, but slightly or not at all bordered; 

 in which the maxillary palpi terminate by a securiform joint or one of an 

 analogous figure, and where the antennae insensibly enlarge. 



Here we have Crypticus and Opatrum. 



2. Those in which the body is narrow and elongated, almost of the same 

 width posteriorly or wider; where the thorax is nearly square, and at least 

 almost as long as it is broad, and where the antenna form a thick club, or 

 are abruptly dilated at the extremity. 



To this division belong Corticus, Orthocerus, Toxicum, &c. 



3. Those in which the body is equally narrow and elongated, and the 

 thorax almost square, but where the antennx are of the ordinary thickness, 

 and are not abruptly terminated by a club. 



The two anterior thighs are stout, and the tibiae narrow and curved, or 

 arcuated. 



The genera are Calcavy Upis, Tenebrio proper, and Heterotarsus. The 

 Tenebrionites are very common under bark of trees, on old walls and the 

 uninhabited parts of houses. 



