MELANISM IN YORKSHIRE LEPIDOPTERA. 



317^ 



fiofc overlook tho fact that our collections do contain specimens which are 

 intermediate, but these I believe Iiave mostly, if not all, been bred from 

 the egg (I hive bred some myself), and only an occasional brood shows 

 thom, and artificial conditions may have had something to do with it. 



Besides Beiularia, we have now in Yorkshire at least thirty species in 

 which melanism has become so strongly developed that in various districts 

 — chiefly in the south-west — black or nearly black speciaieiis of species 

 which in other districts are pale are now regularly obtained. Tliese 

 are : — 



Odoiitopera bidentata 

 Phigalia pilosaria 

 Boarmia repandata 

 Tepbrosia biundulaiia 

 Fidonia atomaria 

 Venutia cambricaria 

 Hybernia progemmaria 

 Oporabia dilutata 

 Larentia multistrigaiia 

 Eupithecia castigata 



„ albipunctala 



Hypsipetes impluviata 



„ elutata 



Cidaria riissata 

 ,, immanata 



Acronycla luegacepLiala 



„ ligustri 



„ rumicis 



,, men3''anthidi3 



Xylopbasia polyodon 

 Apamea ouulea 

 Miana strigilis 

 Agrotis agathina 

 Epunda viminalis 

 Hydrocampa nymphiualis 

 Scoparia mercuralis 

 Tortiix pyrastrana 

 yciaphila virgaureana 



,, octomaculana 

 Diurnea fagella 



In the following of these — llypsipeks iiiiplnviala, Uypsipeles elutata, 

 Acronycta rujnicitt, Xy/o^jhasia poiyodon, Apamea oculea, Miana striyilis, 

 Epunda viininalis, and possibly one or two others — tlic melanism is not of 

 recent development. They have been dark in Yorkshire ever since any 

 interest was taken in Lepidoptera, and consequently, whether they were 

 originally pale with us we are now unable to determine. The othei-s 

 have become dark, or at any rate tiie dark specimens have largely 

 increased in numljers, during the collecting experience of many of our 

 present day lepidopterists. More than this, there are at the present time 

 (juite a number of species of which specimens so much darker than the 

 typical forms are so frequently taken as to indicate that they too are 

 being influenced towards the same end. These include : — 



llepialus heclus (the female) 

 Arctia fuliginosa 



,, mendica 



„ lubricipeda 

 Bombyx quercus (var. callumc) 

 Eiinomos fuscantaria 

 Abraxas ulmata 

 IJybernia aurantiaria 



„ defoliaiia 

 Bubolia palumbaria 

 Cymatopliora diluta 



Xylopbasia rurea 

 Agrotis segetum 



,, tritici 

 I'olia fiavocincta 



„ obi 

 Agriopis Apiiliaa 

 Aplecta nebulosa 

 Hadena dentina 

 Cloantba solidaginis 

 iScoparia cembnc 



and probably many of the Micro-lepidoptera. In two or three of tliese, 

 however (not more), the darkening is more melanochroic than truly 

 melanic. 



It is not necessary for our purpose to-day to detail the histories of all 

 these melanic species ; still, remarks on some of the niDro prominent may 

 tend to elucidate the subject. 



As before stated, melanism was known in AmphyJasis betularia long 

 before it was observed in any other species ; then it seemed to develop in 



