390 Dr. Wallace on the Oak-feeding 
with water, which was effected by placing each larva, while clinging 
to the oak spray, in a bason of water, and leaving him there for 
one minute; and, secondly, to place them out of doors on some 
young oak trees in the garden. This was done by pinning the 
sprays to the oak boughs. After doing this I watered them very 
freely by means of a watering-pot, twice during the day. 
June 27th. They were watered again twice; temperature 70° 
during night, 75°—80° by day ; several larvee were on the ground, 
having dropped from weakness ; others were hanging prone, mo- 
tionless, and flaccid, suspended only by their hind claspers. The 
minute dusky specks had increased into spots, and even blotches, 
which were most numerous in the folds of the segments, leaving 
the middle part of the segment swollen, and of a lighter but 
dirty yellow-green colour; the spots increased to irregular blotches, 
and in some cases the body burst open, emitting a dirty opaque 
putrilage ; in one Jarva which burst open a whitish patch ap- 
peared, as if of mould. 
June 28th. A very heavy rainfall, with thunder ; two or three 
larvee were dead, but they were not so black as those which had 
died before ; some that were on the trees seemed more hvely and 
vigorous; they had eaten the leaves, and their colour was less 
dusky, but the spots had not disappeared, though they seemed 
fainter. 
June 29th. About six dead; the temperature again warm and 
sultry ; the watering by the water-pot was still kept up; the sur- 
vivors look blotchy, only two or three looking at all healthy; in 
some diarrhoea was observed, in others the skin burst ‘open even 
before the blotches appear ; some of the leaves were eaten. 
June 30th. Two more dead ; all the survivors were spotted; a 
heavy shower of rain fell. 
July 2nd. The last two days were showery; only six larve 
were alive, but two of these looked healthy. 
July 8th. Only one larva remaining, but a few dusky specks 
were visible. 
July 11th. The larva was alive, but spotted all over. 
July 12th. Dead; one or two larvae seemed to have been much 
worried by the little black ants, but these larvae were much 
diseased, and exuding a sanious fluid; and it seemed to me, since 
the other larvz were not attacked, that the ants had been attracted 
by the fluids exuding from the bodies of the larvee. 
I will now recount the experience of a lady in Devonshire who 
obtained a batch of about 100 eggs. ‘* My oaks became covered 
