l82 YORKSHIRE NATURALISTS* UNION. 



Melanic and Intermediate Aberrations of Abraxas 

 sylvata {ulmata) in Yorkshire, by W. Hewett {Entomo- 

 logists Record, vol. 9, p. 304): — 'During the present season 

 melanic forms of ^. sylvata {ulmata) have been by no means 

 rare in one particular locality in Yorkshire, and I have 

 secured a number of these, as well as many intermediate 

 aberrations, as the result of four visits paid to the district 

 this season. Messrs. Maddison, Head, Walker, and Button 

 have also obtained these aberrations in some numbers. 

 None of them have been obtained from larvae collected 

 in the neighbourhood of York, as stated by one of your 

 contemporaries, but all were secured in the imago state, 

 occurring amongst the typical form, which in this particular 

 locahty is found in profusion. I" kept a number of melanic 

 females (principally cripples) for eggs, which several depo- 

 sited. The majority of these were fertile. Dr. Riding very 

 kindly undertook to rear them, and in a letter dated Aug. 

 . 24th, says : ' I am glad to be able to write that almost all 

 the Abraxas sylvata {tdmata) have gone down ; there have 

 been three or four pupae on the surface, so there is little 

 doubt but that- the others that have disappeared into the 

 cocoa-fibre have pupated also. There are about ten larvae 

 still feeding, and I think altogether I have not found half-a- 

 dozen dead ones. Not one 'spun a web in the tree,' as 

 stated by Stainton to be the habit of the genus Abraxas.'' 

 I may add that Dr. Riding fed the larvae on wych-elm. We 

 are now looking forward to the rearing for the first time of 

 melanic forms of A. sylvata {uhnata) from the egg. 



' The history of these forms in this locality may prove 

 interesting. Messrs. Head, Walker, and myself have each 

 collected in the locality for years, more especially whilst A. 

 sylvata {ulmata) has been out, and although we have each 

 made special search for aberrations, not one of us had 

 ever observed a melanic specimen in this locality prior to 

 the present year. The simultaneous appearance of a con 



Trans. Y.N.U., 1900 (pub. Dec. 1900). Series D, Vol. 



