REARING ACRONYCTA (cUSPIDIa) TRIDENS. 2H5 



hyhr. italoanglica, Tutt (ochsenheimeri cf x tilipcndulffi ? ). 



PSYCHIDES. 



Fumea, Stphs. 



lii/hr. piingeleri, Tutt (casta j x affinis ? ). 

 Jij/hi . inversa, Tutt (affinis j x casta ? ). 



Rearing Acronycta (Cuspidia) tridens. 



By (Ekv.) C. R. N. burrows. 



Although by no means rare, this insect is always interesting on 

 account of its close resemblance to its relative Acroni/cta psi in the 

 imago stage, and the great difference of the larvtB, and the collector 

 often ponders over the question — What is the difference between the 

 species, and why '? 



Entomologists will await with interest Dr. Chapman's remarks 

 promised to the City of London Entomological Society on March 20th, 

 1906, and will hope that these and the discussion following thereupon 

 may throw some light upon the problem. I suppose that no ento- 

 mologist now-a-days would care to place in his collection specimens 

 about which he was not quite certain as to their identity. To be 

 certain he must at present either rear the insects himself or else accept 

 his insects upon the guarantee of others, x^nd again each specimen 

 must be rigorously labelled, not only with its ordinary data but also 

 with its name. Only then can one feel easy as to the veracity of the 

 two series. 



There can be no doubt but that the ideal method of getting together 

 a good series of both species, is to get the larvfe from different localities, 

 keep them carefully separate, and I have thought, do this (in different 

 years), lest there should be the slightest confusion or mistake. This 

 can be easily done with A. psi, but I have never found A. tridens 

 respond well to searching or beating. No doubt there are some districts 

 more favoured than others by the latter species, but unless one gets 

 the larvffi one cannot know. It is with the purpose of helping towards 

 knowledge and specimens that I am tempted to ask the Editor to 

 accept these notes. A. tridens does not appear to be very common 

 here. I have only once or twice taken a larva, and then lost interest 

 in it, as one does with single specimens of a pretty common species. 

 This year (1905), however, I thought to add to my series, and bethought 

 myself of a plan, which I believe I received from my friend the Eev. 

 G. H. Raynor. The thing is to ho.r any specimen, whether A. tridens 

 or A. })si, whenever and however taken, as long, of course, as it is of 

 the proper sex for the purpose. They will lay readily and abundantly, 

 and the chip boxes containing the eggs are then to be bagged upon 

 any suitable foodplant. If the eggs be fertile, as one hopes they will 

 prove to be, a few weeks will tell the experimenter what is his fortune, 

 for the young larvfe will soon show the special character. In this way 

 one can easily get a stock of whichever species he desiderates, with 

 very little trouble and complete certainty. 



I followed this plan then, this year, at Mucking, and succeeded at 

 once in getting a fine brood of A. tridens. Their life story was curiously 

 brief, for, having hatched on June 27th, they began to emerge on 

 August 20th, and continued to appear until September 7th, when, as far 

 as I know every specimen had disclosed its imago. Never did larvtB 

 give less trouble. In a large bag, they fed up quietly on plum, out-of- 



