INSECTA MADERENSIA. 7 



Somewhat allied to the D. albomaculatus, Lucas, from Algeria (as may be seen 

 by a reference to the splendid work on the insects of that country, published by 

 the French Government, — p. 18. pi. 2. fig. 8), though at the same time with abun- 

 dant specific characters to separate it therefrom. The present Dromius is peculiar 

 to Porto Santo, in which island I captured it in great profusion, fi'om beneath 

 stones, dm'iag April and May 1848 ; as also, subsequently, in December of the 

 same year, and in April 1819. It is found in dry exposed spots of a low elevation, 

 being especially abundant on the level of the sea-shore in the vicinity of the 

 Cidade, and on the open plain of the Campo de Baxo. It is the Porto Santan 

 representative of the D. obscuroguttatus ; and distinct as it is in coloiu^ing from 

 that insect, I am by no means prepared to assert that it may not be, in reality, a 

 local modification of it, brought about by isolation through a long series of ages on 

 a calcareous soil. As such a concession, however, would at once entail a host of 

 difficulties regarding the validity of other " species " (even of European genera) 

 similarly circumstanced ; and siace out of many hundred specimens which have 

 come beneath my notice, not a siagle intermediate liak has hitherto occurred to 

 connect the two, I do not ventiu'e to amalgamate them ; — suffice it to record my 

 conviction, in this brief remark, that if the time ever should arrive in which the 

 real effects of latitude and climate on external insect form are better appreciated 

 than is now the case, the present Dromius, along with other insects innumerable 

 in positions nearer home, vnR in all probability be doomed, as species, to sink. 



6. Dromius obscurogmttatus. 



D. latus atro-subseneus, elytris substriatis macula obscui'issima humerali pallida, tibiis tarsisque piceis. 



Long. Corp. lin. 1^. 



Lehia obscurofjutfata, (Anders.) Diift. Fna Austr. ii. 249 (1812) . 

 Dromius spilotus, Dej. Spec. Col. i. 240 (1825). 



impunctatus, (Kby.) Stepli. III. Brit. Ent. i. 23 (1828). 



ohscuroguttatus, Ericli. Kiif. der Mark Brand, i. 32 (1837). 



Habitat sub lapidibus in montibus superioribus IMaderje, tempore biberno et vernali copiosissimus. 



D. broad, deep black, witb an seneous tinge. Head broad. Prothorax short, subcordate, much 

 narrowed behind. Elytra very faintly striated, with an extremely obscm-e, somewhat oblique 

 patch at the anterior lateral angles paler. Wings obsolete. Tibice and tarsi piceous. 



Apart from its somewhat smaller size and fainter striae, the present species may 

 be at once known from the B. arenicohis by the total absence of pale patches on 

 its elytra, — excepting a most obscure spot, sometimes scarcely apparent, towards 

 their humeral angles. It is a common European insect ; and the Madeii-an speci- 

 mens recede from the ordinary ones in being slightly larger, and in having their 

 elytra more obscurely striated, with the humeral patch less distinct : then- entii-e 

 surface moreover is of a deeper black,— a difference which is especially perceptible 



