CARABlDiE. — CAIIABUS. 47 



Genus XVIII. — Carabus Auctorum. 



Labrum bilobate : mandibles arcuate, with a small tooth in the middle : internal 

 tnaxillary palpi with both joints of equal length, and filiform ; external with 

 the first joint very short, second elongate, third and fourth equal, the latter 

 obliquely truncated : labial palpi with the two basal joints short, third elon- 

 gate, fourth securiform, obliquely truncate : labium short, tridentate : mentum 

 linear, rounded laterally, unidentate in the middle. Antenna; linear, second 

 joint shortest, third cylindric : thorax subcordate, emarginate behind, with 

 the posterior angles prominent : abdomen oval, wings none, or rudimentary : 

 anterior tarsi of males dilated. 



These conspicuous insects fully illustrate the diflicvdty we labour under in our 

 attempts to subdivide natural objects into groups of similar rank and import- 

 ance, as a transient inspection of the genus Carabus, in its present restricted 

 sense, will manifestly render evident ; the structure of Ca. intricatus and 

 auratus (figured in Plate III.) being more dissimilar than that of other in- 

 sects, e. g., Nebria and Helobia, which are usually placed in different genera, 

 or, as some persons designate them, subgenera. Yet, as I do not choose to 

 increase the number of generic names, I shall content myself with merely 

 subdividing the indigenous species into two sections, as, from the paucity of 

 them in Britain, no great advantage would be derived from descending to 

 the consideration of minute sectional characters, however desirable when ap- 

 phed to all the known species : it may be remarked that the majority have the 

 elytra united, while C. cancellatus has them capable of motion, and is fur- 

 nished with long rudimentary wings. 



A. Elytra not sulcated. 



Sp. 1. intricatus. vPlate III. f. 5. — Elongatus, niger, supra cyaneus, thoracis 

 angulis posticis acuminatis, elytris striis tuberculato-rvgosis. (Long. corp. 

 1 unc. — 1 unc. 3 lin.) 



€arabus intricatus. Linne. — Don, xv. pi. 626. Jig. inf. — Stepli. Catal. N'o. 

 61. 



Head black, glossed with violet, with a deep impression on each side, the fore- 

 Head black, rugose : thorax black, opaque, sub-cordate, truncate anteriorly, 

 emarginate posteriorly ; obsoletely transversely striated, with a slender im- 

 pressed longitudinal line : the elytra are black, opaque, convex, much broader 

 than the thorax, thickly and deeply rugose-punctate, without distinct striae : 

 body beneath convex, black, smooth, shining : legs elongate, black : an- 

 tennae black at the base, pubescent and brownish at the tip. 

 This magnificent insect is marked as a native of Britain by Dr. Turton, but I 

 beUeve without any authority, as I have never seen a specimen in any collec- 

 tion which has passed under my observation, neither have I ever met with 

 any individual who has ; but as I have pledged myself to insert all the species 

 which have been introduced into our Ust by my predecessors, it is clearly 

 incumbent on mc to notice this insect. 



