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ON THE BRITISH SUBSPECIES OE CARABUS 

 VIOLA CUUS. 



By ERNST HARTERT, Pn.D. 



Carabus violaceus is one of the most interesting species of the fascinating 

 geuns Carabtts, because it presents a great many local forms, especially iu the 

 Alps, and in its distribution from east to west. 



Carabus violaceus violaceus has the upper surface of the elytra uniformly 

 covered with fine granulations, without any striations, and the margins of the 

 elytra are of a beautiful reddish violet. This form inhabits North-Eastern 

 Germany, eastwards apparently to Russia and Austria, Denmark and portions of 

 Scandinavia. Numerous other forms are spread over the more south-eastern 

 countries and over the Alpine districts. 



In the west, in the plains of West Germany and of the greater part of 

 France, C. v. violaceus is replaced by forms of a totally different appearance ; 

 in these the elytra are sharply striated with about a dozen elevated lines, between 

 which granulations are visible. This is Carabus violaceus purpurascens. One is, 

 at first sight, inclined to think that violaceus and purpurascens are two different 

 species, as they differ so strikingly, and because, according to Erichson and other 

 authorities, in certain parts of South-West Germany both occur in the same 

 localities. Moreover, the forceps of the male is straighter and more blunt iu typical 

 violaceus; more pointed, tajiering, and more curved in purpurascens. We are, 

 however, assured by Paul Born and other specialists that various forms present 

 complete intergradation between the two extremes, and that their distribution 

 is not the same ; it is quite possible that, iu this and other cases, single 

 occurrences of one or the other form in the area of a different subspecies is due to 

 involuntary transportation (with moss, vegetables, etc.), or that such specimens are 

 atavistic aberrations, and we may, for the present, accept the dictum that violaceus 

 and purpurascens are representative subspecies of each other. 



A very fine form, close to purpurascens, but with a greenish golden border 

 to the elytra, is not rare on the French side of the Pyrenees. Mr. Rothschild 

 and I caught it under stones near Canterets (Hantes Pyrenees), and about 

 1500 metres high, near the Hospice de Luchon (Haute Garonne), aud Rondna 

 sent it me from Gedres. 



In England we would expect a form like or near purpurascens, but this is not 

 the case ; British specimens are widely different from the striated forms, and closely 

 resemble violaceus. From the latter (a series from Silesia, North Germany, and 

 Austria, examined) they differ, however, by the elytra being less finely, more 

 roughly, and somewhat more irregularly granulated, thus appearing much less 

 smooth. The forceps of the male is blunt as in German C. v. violaceus, not so 

 much pointed and curved as in purpurascens aud fulgens. The size of the British 

 form is rather variable. Other constant differences 1 have, so far, not noticed. 

 I name the British form : 



