VARIATION. 197 



finer of the two, and here I may remark that it is the result of 

 only one season's experiment. 



Now it cannot be doubted that, under the influence of the 

 long continuance of dry weather and hot sunshine, the species 

 is rapidly developing a local variety, and it appears to me to be 

 a case to illustrate how careful we should be when describing 

 varieties, to note the conditions under which they were evolved, 

 especially when the species under more favourable conditions 

 rapidly reverts to the typical colours. Perhaps similar experi- 

 ments conducted with the British " Carpet Moths " would 

 enlighten us further on the subject. But I leave entomologists 

 to draw conclusions from their own experiments, whether 

 certain forms of variation are due to heredity, to seasonable 

 derangement or artificial environment. The cases cited appear 

 to me to be due to the former, borne from their zone of origin. 

 If we consider the immense duration of time of the earlier 

 geological epochs and their uniform conditions of temperature, 

 we may form a fairly accurate idea of the origin and stability of 

 the colours of insects. In any light we study the question, the 

 value of the results would be greatly enhanced by a series of 

 sound experiments conducted in close imitation of natural 

 conditions, and especially bearing in mind the more important 

 object in view. 



AsHBURTON, N.Z. June, 1891. 



Variation. 



Black Varieties of Boarmia roboraria and Liparis monacha. 

 — When at Mr. Edmonds' extensive larvae breeding-ground at Windsor, 

 I saw, among a number of good things, some very dark Boarmia robo- 

 raria, and several black Liparis iiionadia (which emerged while I was 

 there), and amongst them a black female with only a few white specks 

 near the thorax. I also heard of some black specimens of Vanessa io 

 having been bred, though not then in Mr. Edmonds' possession. I may 

 safely say that any one taking the trouble to go through these grounds 

 will be amply repaid for doing so. — D. H. S. Steuart, Royal College 

 of Science, South Kensington, S.W. 



Leucania unipuncta var. asticta. — I find there is in the Museum 

 here a specimen of L. tmipunda referable to the form asticta, Tutt. The 

 spot at the base of the reniform is not quite obsolete, but it is of the 

 same colour as the wing instead of being white. This specimen was 

 taken in Jamaica by Mr. J. J. Bowrey — T. D. A. Cockerell, Institute 

 of Jamaica, Kingston, Jamaica. August loth, 1891. 



