124 MANDIBULATA. — COLEOPTERA. 



Genus CLXXI. — Ctesias mihi. 



Antenna; as long as the thorax, with the two basal joints robust, subglobose; the 

 six following extremely short, slender and coarctate; the remainder forming 

 an elongate, compressed, tri articulate, serrated club, the basal joint of which is 

 very large, obconic, with the apex truncate and dilated interiorly; the second 

 short, triangular, acute interiorly; the terminal elongate, rather dilated 

 within, and rather attenuated to the apex, which is obtuse. Palpi, maxillary, 

 with the third joint longer than the second, the terminal obliquely truncate: 

 head small, deflexed, slightly produced anteriorly: thorax trilobate behind, 

 the central lobe obtuse, the angles acute : body ovate: legs short and slender; 

 femora rather attenuated ; tibiae simple ; tarsi with the intermediate joints 

 shortest. 



Latreille remarks upon the insects included in this and the fol- 

 lowing genera — and a third species not hitherto detected in Britain 

 — which he has placed as so many sections of the genus Megatoma, 

 " Hujus generis sectione forsan totidem genera constituunt :" — and 

 if the structure of the antennae is to be our guide in the formation 

 of genera, which is allowed to be the case, doubtless the present 

 genus must be detached from Megatoma, and the latter from Atta- 

 genus, the dissimilarity not only of those organs, but of the palpi 

 and of the external form, justifying such a measure : — the serrated 

 club of the antennae, which resembles that of the genus Throscus, 

 at once points out the present genus from Megatoma, from which 

 the dissimilar proportions of the joints of the palpi, the different 

 lobations of the thorax posteriorly, the broader and stouter body, 

 &c, also remove it. 



Sp, 1 . Serra. Niger pubescens, antennis Jlavis, clavd magna compressd, interne 



bis profundi incisd. (Long. corp. if — 2 lin.) 

 De. Serra. Fabricius. — Me. Serra. Steph. Catal. 95. No. 1011.— Curtis, vii. 



pi. 244. 



Black, or piceous, or somewhat castaneous, shining, thickly punctured, and 

 clothed with a short dusky pubescence : thorax above convex, with an im- 

 pression on each side at the base, the lateral margins rusty-piceous : elytra 

 thickly rugose-punctate : legs pale ferruginous or rufescent, with the femora 

 piceous ; antenna? testaceous yellow. 



" The larva," says the Rev. J. Burrell in the Entomological 

 Transactions, " of D. Serra is a curious ferruginous one, living 



