332 Professor E. B. Poulton on colowr-relation 
EXPERIMENTS UPON THE LARV& OF GASTROPACHA 
QUERCIFOLIA (1893-4). 
On July 22nd, 1893, Mr. W. Holland found a company 
of young larvee of this species crowded together towards 
the end of a shoot of hawthorn near Steeple Aston, Oxford- 
shire. They were all the same size, and had evidently not 
long before hatched from a single batch of egos. Thus was 
afforded the opportunity of trying another set of experi- 
ments upon a larva which is known sometimes to assume 
a lichen-like appearance. Furthermore, there was the 
additional interest of testing larval susceptibility to en- 
vironment before, during, and after hybernation. The 
food-plant employed throughout was hawthorn. The 
present writer 1s responsible for the starting of the experi- 
ments, the arrangements for hybernation,and the comparison 
of larvee on September 21st, October 3rd to November 3rd, 
March 26th, April 27th, May 7th and 25th. The other 
records were chiefly made by Mr. W. Holland, in much less 
part by the present writer. 
I. G. querevfolia. 
July 28th, 1893. Fifteen larvae of quercifolia placed 
with intensely black twigs of the Turkish oak (Quercus 
cerv2s), intermixed with their food- plant, hawthorn. They 
were re-fed and examined on the following dates. 
August 1st. Twelve larve on the green leaves and 
shoots, 3 on the black twigs. All blackish-grey in colour. 
August 5th. Four larvee on the leaves and shoots, 11 on 
the black twigs. 
August 9th. Three larvee on the leaves and shoots, 12 
on the black twigs. 
August 14th. Fifteen larve counted; all on the black 
twigs. The colours were black and white with a little 
grey. 
August 19th. All 15 larve on black twigs. 
August 22nd. All 15 Jarvee on black twigs. 
August 31st. All 15 larvee on black twigs. The larvae 
were now much blacker, but white markings were still 
present. 
September 4th. Fifteen counted. 
September 7th. Fifteen larvee on black twigs. 
September 9th. Fifteen larvae on black twigs. 
