( yar 3} 
tent form of markings—caused by pupal temperature are of 
course well recognised, and these differences are fully ex- 
emplified in the exhibits. But I think they show also other 
differences partaking of a structural character. Those which 
have been cooled appear to me to be more strongly den- 
ticulated, though, before fully accepting this view, I think 
there should be careful measurement; and there is certainly 
a difference in the thickness of the scaling, as may be per- 
ceived by holding them up to the light, those forced appearing 
more opaque than the others, and having a smoother surface. 
“T should perhaps mention that the imagines I exhibit all 
seemed healthy and vigorous, and that, besides these families, 
I have many others that appear to show similar results, and 
in no one of these other families, of which [ have a large 
number, have I been able to observe any directly opposite 
results. I should be very glad if those who have the op- 
portunity would test the results, especially as regards mass, 
and suggest that this might be done by weighing a large 
number of forced pupae and of cooled pupae, shortly after 
pupation, and again shortly before emergence. The great 
difficulty here would be with the forced ones, as their pupal 
period would be only about ten days, but it is no greater 
than close watching could cope with. The summer pupae, 
producing the summer phase, are much more amenable to 
temperature than those pupating in autumn, and I should be 
happy to supply eggs this spring to those who have the 
means of trying this experiment accurately and are willing 
to do so. If I had consulted only my own reputation I 
should have held back this paper until I could have made 
further research, with particular reference to the points on 
which I have suggested further inquiry, but I am afraid that 
if I waited for that it might never be done; and I do think 
that there is sufficient in the facts I have put forward to 
justify me in bringing the matter before the Society as one 
worthy of consideration and of further observation.” 
There was a short discussion on the subject, in which the 
Rev. G. Wuzeter, Dr. Lonestarr, and Dr. CHApMaN joined. 
Srerzoscoric Pxorocrara.—Mr. H. Main exhibited a 
stereoscopic photograph of the cocoon of Chirysopa flava, 
