ON THE VARIATION OF INSECTS. 243 



Variation," or any other name ; the shorter the better. It should 

 be international in its operations. 



John T. Carrinqton. 

 London, September 21, 1889. 



ON THE VARIATION OF INSECTS. 



By T. D. a. Cockerell. 



(Concluded from p. 229.) 



The phases of variation, briefly described in the previous 

 parts of this paper, will probably be found to include most of 

 those to which insects, and especially Lepidoptera, are liable. At 

 present, and in the limited space of a magazine article, it is 

 impossible to treat the subject in any degree of completeness, so 

 I trust that omissions of many important and well-known varieties 

 from the list will be forgiven. Under colour-varieties, those 

 occurring in the Coleoptera are well deserving of lengthy treat- 

 ment, such as the variations in the metallic colours of the 

 Carabidae, the markings of the Coccinellidse, the colours in 

 Donacia, &c. Mr. T. H. Hall has kindly sent me some very 

 interesting notes on the variation in British Coleoptera, from 

 which I select the following, as illustrating the principal phases 

 of variation to be noted : — 



'' Pterostichus. — It is very noticeable that many species of this 

 genus vary from black to brown or testaceous ; the light specimens 

 seem chiefly to occur, in my experience, under stones, &c., in 

 winter. I put them down as immature. Harpalus csneus, F. 

 {proteus, Payk.). — Varies from a brilliant metallic shining green 

 insect to one quite dull and brown, with the slightest sheen of 

 green on its elytra ; the dull variety seems somewhat local, and 

 occurs in singles ; some specimens are rich bright coppery 

 colour; the variation is in colour of elytra, the thorax, &c., being 

 green, but varying in brightness. Coccinella variabilis, F. — A 

 strikingly variable species ; there is a dark and variable variety, 

 with yellow spots ; there appears to be a uniformly parallel 

 variation of thorax and elytra. C. 11-punctata, L., and C. 

 7 -punctata, L. — Vary in size and definition of spots on elytra; 

 the light coloured ones have smaller spots than the dark ones. 

 Typhceus vulgaris (== typliceus, L.). — Is very variable in size and 

 appearance ; out of a number found in one locality no two are 

 alike ; the female varies in rugosity of front of thorax ; in the 

 females the thorax is produced into horns of variable size ; there 

 is a variety of male and female which is brown instead of black. 

 Callidium violaceum, L. — Amongst many specimens found at 

 Wormwood Scrubs, London, the males, which are of much 



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