LUCANIDyE. DORCUS. 165 



Genus CLXXXVII. — Dorcus, MacLeay. 



Antenna? shorter than the thorax, the basal joint about half their length, clavate, 

 second short, slender at the base, clavate ; the four following shorter than the 

 second, the last of them being slightly produced in its inner edge, the re- 

 mainder forming a somewhat perfoliated club, the terminal joint of which 

 is large and semicircular. Palpi, maxillary elongate: labial very short: 

 mandibles short, dentate inwardly : labrum distinct : mentum semicircular : 

 flat, with the anterior margins entire, straight : labium bilobed : head very 

 broad, transverse: thorax with an obscure dorsal channel, slightly margined; 

 the lateral margin straight: body depressed; rounded at the sides: scutellum 

 triagonal, slightly rounded posteriorly : legs short, stout : anterior tibiae irre- 

 gularly serrate externally, intermediate and posterior with a tooth at the 

 outer edge, the apex of all spurred : tarsi short. 



Dorcus is evidently a distinct genus from Lucanus ; and although 

 there is a little external similarity between the indigenous species 

 and the female of Lucanus Cervus, it may be known by the width 

 of the head, the evident labrum, the entire lateral margin of the 

 thorax, the less dilated anterior tibise, subperfoliated antennae, &c. 



Sp. 1. parallelipipedus. Niger, mandibulis longitudine capitis; dente medio 

 elevato, labro late truncato, superficie totd subtilissime punctata : aut, superne 

 rugoso-punctatus labro emarginato, capite bituberculato ; fcemina. (Long, 

 corp. 9 — 14lin.) 



Lu. parallelipipedus. Linne. — Don. viii. pi. 264. — Do. parallelipipedus. Steph, 

 Catal 103. No. 1086. 



Dull black : head very finely punctured, nearly as wide as the thorax, retuse 

 anteriorly, with the labrum broad, truncate; mandibles stout, acuminated, 

 with an elevated obtuse vertical tooth in the middle : thorax finely punctured 

 on the disc, more thickly so on the lateral margins; elytra scarcely so wide 

 as the thorax, very thickly and finely rugose-punctate. Female with the upper 

 surface rather more shining, closely and deeply rugose-punctate, especially on 

 the head and thorax, the former of which is much narrower than the latter, 

 and has two approximating elevated tubercles on the forehead ; the labrum is 

 small, transverse, deeply emarginated and ruggedly punctate ; the mandibles 

 are shorter than in the male, with an obsolete not elevated tooth in the 

 middle ; thorax more convex. 



Found in old decayed trees in the woods about Shooters' Hill, 

 Eltham, Chisselhurst, Birch-wood, &c, and in the neighbourhood 

 of Hertford. " Occasionally, though not frequently, found in 

 various places (near Swansea)." — L. W. Dillwyn, Esq. " Common 

 in pollard ash trees, in the neighbourhood of Bottisham and Ely." 



