65 



Lotus that I potted up for them after the bulk of the mischief 

 had occurred. I hope that Mr. Carr will be more success- 

 ful with his larvae and get a fair number through to the 

 perfect state. 



" In any case the fact is now well established that trifolii 

 and filipendulce do, only occasionally perhaps, cross in a state 

 of nature. At Northwood the two species occurred together, 

 but I never saw an instance of cross-pairing in that locality. 

 As in the Surrey locality, the colony of each species was not 

 far removed one from the other, but there was this differ- 

 ence in the two cases. In the Middlesex district it was 

 filipendulce that was observed on a portion of the trifolii 

 ground, whereas in Surrey it was trifolii that had invaded 

 the filipendulcE colony. Possibly, if search had been made 

 among the Middlesex filipendulce, mixed pairs might have 

 been found ; unfortunately this was not attempted. 



" As has been already stated, some specimens taken on the 

 filipendulce ground in Surrey, and, I may add, also bred from 

 cocoons obtained there, were of the hippocrepidis form, and 

 I cannot see that they are separable in any way from ex- 

 amples of the same form taken with typical filipendulce in 

 May and June at Northwood. If other evidence were 

 wanting, these July and August captures would prove that 

 the form hippocrepidis is not confined to the May and June 

 filipendidce. In his masterly treatment of the Anthroceridae 

 (Zygaenidge) Mr. Tutt ("Brit. Lep.," i. pp. 414 — 546) devotes 

 fully fifty-eight pages to an elaborate and exceedingly in- 

 structive dissertation on trifolii and filipendulce. He would 

 seem to consider that we have two well-defined forms of 

 trifolii, and he deals with hippocrepidis, Steph. {tutti, Rebel) 

 as though it were specifically distinct from trifolii ; but so far 

 as I am able to follow his remarks it would seem that he is 

 not very strongly convinced that hippocrepidis can be separ- 

 ated, as a species, from filipendulce. Any way, the evidence 

 he is able to adduce does not lend very much support to 

 the suggestion that it is distinct. 



" Formerly I was inclined to doubt that the form referred 

 to as hippocrepidis was the result of a cross-pairing, but in 

 the light of recent observations I find that I must modify 

 that view\ A fact of some considerable significance is that 

 wherever filipendulce and trifolii occur at the same time, in 

 a common area, and sufficiently near for the two species to 

 intermingle, there we find the form hippocrepidis in some 

 numbers. So far as my limited opportunities of investigat- 

 ing the matter permit of any conclusion being arrived at 



5 



