95 



interesting data, and it is very remarkable how close the various 

 records correspond. Thus in Russia it is met with in the Moscow 

 district to 59° north latitude. It occurs in Denmark and in Sweden, 

 at Oster Gothland, also 59" N. latitude, but there is no record of 

 it in Norway ; while in our own country, as we all know, it extends 

 to the Orkneys, which are intersected by the 59° N. latitude; but 

 although the Shetlands have been systematically worked for some 

 years past, no trace of it has been found there. The limits of its 

 range, therefore, appear to be from 30^ to 59*^ north latitude and 

 from 37° east to 11° west longitude, or, in order words, from Algeria 

 in the south to the south of Sweden in the north, and from Syria 

 in the east to Ireland in the west — a somewhat restricted area, 

 embracing a comparatively small portion of the northern temperate 

 region, and it will be seen that the British Islands form its 

 north-west limit. 



Coming now to the second part of the question — variation, — it 

 may be convenient to consider it under two heads, namely, general 

 and local. It is an interesting fact that many species are far more 

 prone to variation in the British Islands, or limited portions of them, 

 than in other parts of the area which they inhabit. T. comes is no 

 excepiion in this respect ; not that it does not show forms varying 

 from the type in other places, as we are reminded by the fact that 

 names have been given to sundry forms by Continental authors, 

 under the impre'sion that they have been applying such names to 

 distinct species ; but nowhere do we find variation so frequent, so 

 local, or assuming such extreme forms as in Britain. There is, 

 however, throughout the whole geographical range of the species a 

 tendency to modification of both colour and markings, increasing in 

 intensity with its north-westward range, especially with regard to 

 colour. 



Of the series that I have had the opportunity of examining, the 

 most uniform are from the Asia Minor district. The individuals of 

 which they are composed are clay-coloured, or perhaps it would be 

 more correct to say grey with an underlying reddish tone, and show 

 but little difference in intensity of colour; the variations in markings 

 are also trivial. In Central Europe some examples show a more 

 decided reddish-grey tone, and the markings are not infrequently in 

 somewhat stronger contrast to the ground colour, the effect occa- 

 sionally being heightened by a pale outlining of the stigmata. In 

 Denmark a "brick-red" form is said to occur, but I can find no 

 mention of any special form from the adjacent Swedish locality. 



Throughout England and Wales, as we all know, there is a 

 large amount of colour variation, and the ornamentation is very 

 diverse in pattern ; but it appears to be universal, no particular locality, 

 so far as at present ascertained, producing any special form not 

 found elsewhere, except the Scilly Islands prove an exception. Here 

 a form having unusually dark, sometimes almost black, scalloped 

 transverse lines occurs. It is not the only form that occurs in these 



