INSECTA MADERENSIA. 73 



transversum, antice profunde emarginatum et dente medio integvo instructum. Ligula cornea, 

 apice subrotundata ; paraglossis siiblinearibus, earn parum superantibus. Pedes robusti : tarsis 

 anticis in maribus (II. 6 c) articulis primo et secundo dilatatis (iUo magno siibquadrato) : -un- 

 guiculis simplicibus. 



The immense genus Bembiclium, with its numerous subdivisions (proposed suc- 

 cessively as genera by Megerle, Ziegler and Leach), would seem prima facie to 

 include many well-defined types of form ; nevertheless the sections which the 

 several modifications tend to compose merge into each other by such slow grada- 

 tions, that, like the divisions of Pterosticlms, it is not possible ia a general arrange- 

 ment to ujihold them. In the structure of their oral organs they present, inter se, 

 scarcely the slightest difference, every one of them being moulded on a pattern so 

 nearly similar as to be almost coincident. The minute, subulated terminal joint 

 of their palpi, the entire central tooth of their mentum, and the largely dilated 

 basal articulation of their two anterior male feet are the principal distiactive 

 features which the group displays ; — the fii'st of which moreover is clearly the 

 most imjiortant, as ser^dng even of itself to isolate the Bembidiades from the 

 whole of the other subfamilies of the Carabidce. In their habits the species are 

 essentially subaquatic, being peculiar to moist spots, and especially abundant 

 beneath stones and shiagle at the margins of ponds and streams. 



(Subgenus TACHTS, Ziegl.) 



56. Bembidivun bistriatum. 

 B. fusco-piceum depressum, prothorace subcordato angulis posticis subrectis, elytro singulo striis 



duabus suturalibus punctoque impresso, antennarum basi pedibusque testaceis. 

 Long. Corp. lin. |. 



Elaph'us histriatus, (Meg.) HvtSt. Fna Aitstr. ri..2Qo (1^12). 

 Tachys minutissimus, (Leacli) Steph. III. Brit. Ent. ii. 7 (1829). 

 Bemhidium bistriatum, Dej. Spec, des CoZ. v. 42 (1831). 

 , Heer, Fna Col. Reh. 123 (1841). 



Habitat Maderam, vel ad margines rivulorum, vel super oras rupium humidarum exstantes, inter 

 muscos lapillosque degens, a vere novo usque ad autumnum, sat vulgare. 



B. minute, not very shining, depressed, and brownish-piceous ; sometimes almost ferruginous, or 

 even with a vei-y slight testaceous tinge. Prothorax subcordate, the posterior angles nearly 

 right angles ; vrith a deep dorsal channel ; and an impression on either side at the base. Elytra 

 ovate ; with two distinct striae on each near the sutm-e, the outer ones being evanescent ; and 

 with a single, rather distinctly impressed point on the disk of each before the middle. Antemice 

 infuscate ; their basal joints, the apex of the terminal one, the palpi and the legs testaceous. 



Rather a common insect beneath small stones and moss on the damp ledges of 

 the rocks, and amongst loose shingle by the margins of the trickling streams, both 



