ixxcevit, xxvii, xe) xen) (9!) 
Wednesday, November 7th, 1906. 
Mr. H. J. Lucas exhibited a photograph of Panorpa 
germanica, practically immaculate, taken by Mr. E. A. 
Cockayne, a Fellow of the Society, at Tongue, Sutherland- 
shire, now in the Hope Museum, and a typical form for 
comparison, corresponding apparently to the borealis of 
Stephens. He also showed a series of P. germanica to 
illustrate the range of spotting on the wings of both sexes, 
with two ¢ ¢s and two @ 9s of P. communis; and a pair 
of a third species, P. cognata. The first two species are 
common ; the third scarce. 
Dr. F. A. Dixy exhibited several specimens of Pierine 
butterflies in illustration of melanism, and made the following 
remarks :— 
‘«‘ At the recent meeting of the British Association in York, 
much interest was aroused by Mr. Porritt’s paper and exhibit 
on the subject of melanism. It has occurred to me that an 
illustration of some of the general conditions under which 
white and other kinds of pigment may be replaced by black 
might possibly aid in the consideration of the more special 
question as it affects the insect-fauna of these islands. With 
this view I have brought some selected specimens here to-night, 
and propose, while enlarging the scope of inquiry in one way, 
to narrow it in another by contining my illustrations to the 
group of Pierine. 
‘“‘ A substitution of dark pigment for light may take place— 
““(1) Between allied species, as Belenois mesentina, Cram., 
and B. raffrayi, Oberth. 
‘“‘(2) Between nearly-related forms of the same species, as 
Eronia cleodora, Hiibn., from East London, and £. cleodora, 
f. dilatata, Butl., from Mombasa. 
(3) Between the sexes of the same species, as Delias 
iyerna, Butl., ¢ and @. 
“(4) Between individuals of the same sex of the same 
species, as the ordinary and ‘white’ form of Colias electra, 
Linn., ?. 
“It is often possible to trace a connection between dark 
