NOTES ON TUE VAKIATION OF Sl'ILOSOMA MENDICA. 189 



form, have been obtained and retained for protective purposes, and that 

 the pure white males are as much a development in a special direction 

 suited to special localities and conditions, as are the dark males of oiir 

 central Eurojjean hedgerows, coppices, and woodsides. 



Since the above was written, Mons. A. von Caradja has published 

 in Soeietas entomologica, vol. ix., p. 49, another article on this interesting 

 subject. His article is called " Sjnlosotaa mendica, CI. var. (et. ab. ?) 

 (? Standfussi, Caradja," and he writes : — " By this name I denote tlie 

 hybrid form, obtained by crossing the female of S. mendica, with the 

 male of its variety, rustica. The female of this hybrid naturally does 

 not differ from the females of the type ; the male, however, is exactly 

 intermediate in colour between the dark smoky-brown male of mendica, 

 and the milk-white male of var. rustica ; the wings, thorax and ab- 

 domen, both on the upper and under sides, are of a ver^^ peculiar grey- 

 brown tint, which appears something like a faint pearl-grey cloud 

 spread over the white ground colour. The ordinary black spots on the 

 fore and hind- wings contrast strongly with the gi'ound colour. This 

 new and interesting form, which occurs in nature, I name in honour of 

 my highly-respected friend Dr. Max Standfuss of Zurich. All my last 

 year's broods were unfortunately largely decimated by " pebrine," so 

 that I only obtained a single pair of this crossing from 250 larvas. 

 This year I hope to obtain better results." 



" I may here mention some extremely important facts. The crossing 

 of males of var. rustica with females of mendica, is at all events fruitful ; 

 every egg yields a larva. On the contrary, of females of var. rustica 

 crossed with males of mendica, only 0"15 per cent, produced larvse, and 

 all of the first crossing failed." 



" With regard to the hybrid copulation between females of S. 

 luctuosa, H.-G., and males of var. rustica, reported upon last year, I have 

 to report that this year I have obtained entirely different results, which 

 ]3roves that the results of a single experiment are not always to be relied 

 upon. From five crossings I did not obtain a single larva ; but from 

 the sixth I obtained 141 larvae, which developed vigorously, the first-laid 

 eggs being those which yielded the larvae, whereas the remaining 194 

 eggs proved infertile. The reversion of the sexes in this crossing, viz., 

 the pairing of male luctuosa with female var. rustica, and also male 

 luctuosa with female mendica, were entirely unfruitful." 



The pairing of S. mendica with its variety rustica was carried to a 

 successful issue some years ago in Britain by Mr. Adkin. It would 

 appear that the single male cross obtained by Mons. Caradja (he only 

 bred two moths, and describes both sexes) is not unlike many of our 

 purely-bred Irish males. IIow far Ireland is an area where the type 

 and var. rustica overlap has not yet been determined, dark males not 

 having yet, I believe, been recorded from Ireland. 



The rearing of true hybrids between S. mendica and *S'. luctuosa, adds 

 another to our already long list of hyln'ids obtained from allied species. 

 It would he interesting to know whether S. luctuosa will cross success- 

 fully with typical S. mendica, or only with var. rustica. If only witli 

 the latter, the fact would have a strong bearing on the ancestral furin 

 of the genus. 



