Perhaps no subject in connection with Lepidoptera lias 

 proved of greater interest to Yorkshire lepidopterists, and 

 especially to those of the Western division, than Melanism. 

 Towards twenty years ago, it began to be noticed that 

 various species of which a black or nearly black specimen 

 iliad occasionally been taken, were producing these dark 

 forms in increasing numbers, several of them rather rapidly. 

 Long- before then, indeed, a perfectly black form of Ainpliy- 

 dasis betiilaria was well known, but at that time was so 

 comparatively seldom taken as to be regarded as a rarity. 

 Now it has not only become the dominant form, but in 

 probably most of the South West Riding area has practically 

 altogether ousted the original pale ordinary form. In the 

 Huddersfield district, I have only seen one pale specimen 

 during the past eight or nine years, and a typical specimen 

 is quite a rarity now compared with what the black form 

 was even in the time of my collecting- experience. Other 

 -species which are going rapidly in the same direction are, 

 Pliigalia pilosaria^ Boarmia repaiidata^ Tephrosia biiindidaria^ 

 Hybemiia progeinmaria^ Oporabici dilutata, Larcntia miilti- 

 slrigaria, Them variaia, Acronycta rumicis^ Polia c/u\ 

 Hydroca>iipa iiyinphcealis, and Diiiriiea fagella, and in some 

 of these indeed in the South Western division, the black 

 .specimens seem already to preponderate. Besides these 

 there are several species which, although comparatively pale 

 in most counties in Britain, have been darker in Yorkshire, 

 so far as we know, ever since any interest was taken in 

 lepidoptera. Among- them may be mentioned Boarmia 

 rhomboidaria , Scodiona belgiaria, Mclanippc tristata^ Cidaria 

 fesfata, Notodonta cainelina, Notodonta dromedarius^ Notodonta 

 dodomca, Acronycta leporina^ Apaniea oculea (in the South 

 West), Miana strigilis, Epunda vitninalis, etc., and whether 

 they too were originally pale with us, we are now unable 

 to determine. The species in our county in which Melanism 

 has become so strongly developed that in various districts 



Trans. Y.N. I'. Series D, Vol. 2. Dec. 1903. 



