120 THE ENTOMOLOGIST. 
folded double, which should have previously been soaked in warm watef 
containing a little carbolic acid (about one teaspoonful to a quart of water), 
and well wrung out, so that no water will afterwards drip from them. The 
insects may then be placed on the flannel. Carbolic is an important item, 
as it not only prevents mould, but kills germs which may be in the speci- 
mens. It is rather difficult to set down an average time for relaxing, as 
there are so many things which tend to retard the softening process. A 
great deal depends on how the insects have been killed, and what treatment 
they may have been subject to afterwards. A few days ago I had a 
~ collection in papers, which appeared to have been subjected to the influence 
of some essential oil, causing the specimens to be almost proof against 
vapour, some of them taking as long as a fortnight to relax. Under 
favourable conditions, and in a warm temperature, Lycenide and small 
moths will take about twenty-four hours; the smaller Nymphalide, two 
days. The most difficult of all are Prepona, Charaxes, &c, which should 
always be thoroughly relaxed before attempting to set them. Delicate 
green moths require a little different treatment: carbolic acid should not 
be used for these, as it takes away the colour, neither must the specimens 
touch the flannel; they should be pinned or placed on a sheet of paper 
over the flannel. Relaxation may be hastened by placing the box near a 
fire, but a medium temperature is always preferable—A. Cant; 54, Wey- 
mouth Street, Portland Place, W. 
GREEN AND Brown Pura or Papitio.—Theoretically, Mr. Cockerell’s 
views respecting the time of emergence of the Papilionide are interesting 
(Entom. 93), but it certainly does not hold good with P. machaon, as both 
forms of pupe pass through the winter; and as the green form is more 
abundant than the brown, the coloration in this species is not apparently 
produced for protective resemblance. Last spring I obtained many pupe 
of machaon trom Cambridgeshire, from which imagines commenced to 
emerge in May, and continued to do so until the middle of August, with the 
exception of four, three being of the green form and one of the brown; all 
four are still alive, having passed two winters at least. The coloration in 
the pups of different genera is undoubtedly caused principally by the 
colouring of the immediate surroundings during the process of pupation, 
but is not constant. I have obtained differently coloured pupe of the same 
species of Pieris, which had all pupated under precisely similar conditions, 
and at the same time. But yet | know they do very frequently partake of the 
surrounding colour, and agree very closely therewith in both tone and hue; 
for instance, P. brassice, when attached to a cabbage-leaf, will not only 
exactly assume the colour, but will also lose the usual black markings.— 
F. W. Fronawxk; Balham, 8.W., April, 1592. 
GREEN AND Brown Pup® or Papriiio.—Last August, while in 
Norfolk, I obtained about two dozen larve of P. machaon, which all 
pupated at the beginning of September, and have remained in that stage 
till now. In these there are three distinct shades of colour to be noticed, 
viz., a very dark brown (almost black), a lighter flesh-coloured, and a bright 
green ; all these were reared under as nearly as possible the same conditions 
with regard to food, light, &c., and the green ones do not seem to have 
chosen a more illuminated position for their metamorphosis than the darker 
ones (in fact, in some cases, the reverse); and I should like to know if this 
difference in colour can be accounted for by the fact that the green pup 
pupate on the food of the larve, whereas the darker pupe are placed away 
