(Gasoocy ) 
difference between the English and Scotch races; and 
Trichopalpus fraternus, from Wicken Fen, a species new to 
the British fauna. 
Papers. 
Mr. F. MerririeLp read a paper, illustrated by a large 
number of specimens, on “The Colouring of Pupe of P: 
machaon and P. napi caused by the exposure to coloured 
surroundings of the larvee preparing to pupate.” 
It had generally been considered that the larva of P. 
machaon was insusceptible to its surroundings when at the 
period of pupation, but at the instance of Prof. Poulton he 
had tried experiments last summer which proved that this was 
not the case. Of eleven pupe of the first brood obtained in 
July, six larvee were set to pupate on dark sticks; four of 
these were of the bone-coloured form, but a fifth was inter- 
mediate and the sixth fell to the earth, where it formed a 
green misshapen pupa. Of the five larve set to pupate on 
white sticks of peeled willow, four pupated on them and were 
all green, the fifth pupated on the white muslin top and was 
bone-coloured. Of seven other pupe that were found to have 
attached themselves to the stems of the green carrot tops on 
which they were fed, six were green and one bone-coloured. 
This made a strong case, but experiments tried on a larger 
number of the larve of the second brood in September were 
conclusive. Of 16 pupated on black paper or dark sticks, 
all but one were bone-coloured, and most of them dark, four 
that pupated on green carrot tops were all green, and of 19 
others that pupated on yellow or orange all but one were 
green. Various intermediate colours gave mixed results ; abso- 
lute darkness produced five bone-coloured pup but of a pale 
hue. Seventy-two pupe had been obtained, and all these were 
exhibited, as were the pupz or pupa-cases of the eleven of the 
summer brood that had pupated. Several hundred pupz of 
the second brood of P. napi were also exhibited, and these 
were shown to be exceedingly sensitive. Of ten on black 
paper all were dusky with much spotting of dark brown, so 
were seven out of eight on dark sticks, the eighth being 
green. Of twelve on green cabbage leaves or on the glass of 
the bottle containing them the majority were green or 
