CARABID^l. 17 



a single species. There are few questions, however, bearing on our 

 present subject, which are more difficult to decide than the amount 

 of importance which should be attached to the many slightly differ- 

 ing forms which arrange themselves around the D. sigma ; and unless 

 therefore we are prepared to acknowledge an indefinite number of 

 closely allied species, I think we shall be compelled to regard that 

 insect not merely as eminently variable but as varying (more or less 

 appreciably, though doubtless within fixed limits) in nearly every 

 country and district in which it is found *. 



Taking it for granted therefore (as in the case of the D. ellipti- 

 pennis) that the numerous modifications to which I have just referred 

 are but local states of the sigma, I may add that the species has been 

 taken in Madeira proper, Porto Santo, and the Deserta Grande, of 

 the Madeiran Group, and in Grand Canary and Teneriffe, at the Ca- 

 naries. It ascends occasionally to a very lofty altitude, indeed in 

 Teneriffe to nearly 9000 feet above the sea, in which elevated district 

 it represents the " var. /3 " (found on the Cumbre adjoining the 

 Canadas) of my Canarian Catalogue. 



42. Dromius umbratus. 

 Dromius umbratus, Woll., Append, hvj. op. 6. 

 Habitat Maderenses (Mad.), rarior ; a Dom. Bewicke parcissime lectus. 



Two examples of this Dromius, which were captured by the late 

 Mr. Bewicke in Madeira proper, are all that I have yet seen. The 

 species is closely allied to the D. sigma ; but it appears to be consi- 

 derably larger, with the head and pro thorax wider and more deve- 

 loped, with the elytral fascia very much thicker and straighter (or 

 less dentate), and with the limbs more rufescent (or less testaceous). 

 It is certain, however, that further material is required, in order to 

 ascertain that these various characters are constant. 



* Two Teneriffan examples, however, which were collected by the Messrs. 

 Crotch, if not specifically distinct from the sigma, appear to be worth recording 

 as representing at any rate a very remarkable variety. They differ in the head 

 and prothorax being a little more developed, in the latter being also very appre- 

 ciably longer and of a paler testaceous hue, and in the elytral fascia being a 

 great deal thicker and less dentate. They have much the general colouring of 

 the D. oblitus, Boield., of more northern latitudes ; but their head is rather 

 larger, their prothorax considerably more elongated, and their elytra are more 

 conspicuously striate. The state (or species ?) of which they are the exponents 

 may be enunciated as follows : 



Var. y. longicottis. Capite prothoraceque paulo majoribus, hoc sensim longiore 

 et clare test ace o, elytrorum fascia multo crassiore, rectius transversa vel multo 

 minus dentatu, 



