274 [May, 



EESULTS OF EXPERIMENTS IN REARING TEPHROSIA CREPUS- 

 CULARIA AND BIUNDULARIA, WITH REGARD TO VARIATION. 



BY J. T. D. LLEWELYN, M.A., E.L.S. 



Some years ago, Eobert Stafford and I tried and published an 

 experiment in rearing the dark smoke-coloured variety of Tephrosia 

 crepuscularia, and I now offer a few remarks on a repetition of this 

 experiment on this and another species of the same genus, viz., T. 

 biundularia, in which the variation is still more pronounced and 

 distinct. 



Finding the variety of crepuscularia in a wild state, in a propor- 

 tion of 5 per cent, to the type, we selected ova from a fine dark female 

 moth, and, rearing them, were enabled to mate a dark pair, and thus 

 obtain ova from two dark parents : in the next year we had a larger 

 proportion of the dark smoky variety, and, repeating the selection of 

 parentage, secured the union of darkly-bred dark parents, and thus, 

 in 5 years of selected parentage, we were rewarded with a batch of 

 97 perfect insects of Teph. crepuscularia, all, without one solitary 

 exception, of the dark smoky variation. 



On a second trial of this same process, and in the third year of 

 its satisfactory progress, we lost the whole lot from the ravages of the 

 ichneumon flies, but nothing daunted, and favoured by circumstances, 

 a fresh trial has this spring resulted thus. In the year, a batch of 

 250 insects hatched out from ova obtained from dark parents, but 20 

 have reverted to the original type. 



In the case of Tephrosia biundularia, the variety is black, with 

 the subterminal line clearly and conspicuously pencilled out in white, 

 and this form of variation seems far more scarce with us than the 

 corresponding form in crepuscularia. "We have previously reared 

 batches of this species, crepuscularia — both the spring and summer 

 broods — but have only succeeded in obtaining a few specimens of the 

 dark variation ; last year, however, a dark female gave us a goodly 

 batch of ova, and we are now hatching them out with the satisfactory 

 result of having secured some twenty of this fine dark form ; of these 

 we have induced three pairs to mate, and have thus, at last, secured 

 the wished-for darkly-bred ova. 



I have used Doubleday's Nomenclature. 



"Will any of your correspondents kindly tell me if the other 

 species of this genus are liable to similar variation ? 



I have plenty of the variety of crepuscularia in duplicate, should 

 it be acceptable to your readers who would care to have it, but very 

 few of biundularia. 



Penllergare, Swansea : 



April 12th, 1882. 



