between lepidopterous larvm ami their surrouTiclings. 365 



with grey, 1 smaller and darker with less grey. Two 

 smaller larvfe, probably in the 4th stage, or perhaps at 

 the beginning of the 5th, were respectively lightish and 

 darkish-brown. 



June loth. One of the darkest larvtehad become mature 

 and was removed. 



Jicne ISth. One of the darkest larva? become mature and 

 was removed. 



June 20th. Two very dark larvae mature and removed. 

 One very small one dead. Of the 6 in the last stage, 4 

 were very black, in 3 cases overspread with dull greyish 

 patches ; 1 was greyish on the dorsal surface, lighter 

 grey elsewdiere ; the 6th and smallest someAvhat resembled 

 that last described. 



June 26th. All had become mature except that last- 

 mentioned, which had become a dark brownish-black. 



Jidy 2nd. No further change. 



July 12th. The larva bad become mature and was 

 removed. 



CONCLUSIONS. 



The power of the black surroundings is evident, the in- 

 fluence of the green being only seen in the occasional grey- 

 ness on the black larva3,and especially in the one larva which 

 Avas entirely grey. The brownish shade of the larva which 

 Avas the last to reach maturity is unusual on the twigs of 

 Turkish oak. These probable effects of the green on the 

 larA'se Avhich had been longest exposed to the influence of 

 black (being the last to pupate), are contrary to the results 

 observed in the other experiments. 



B^. A. hetularia. 



June Srd. Five hetularia larvaa in green surroundings 

 up to the end of the 4th stage were transferred to 

 black. They were changing the 4th skin and 20'5 mm. 

 long. 



J^ine 5th. One larva, a green one, was on a black twig, 

 the others on the leaves. Four were brownish-green and 

 1 medium brown. All were advancing in the 5th staoe 

 and about the same size. 



June 20th. Three large in the 6th stage, 1 dark smoky- 

 black ; 1 greyish smoky-black, and 1 intermediate, greenish- 

 broAAm. One small one dead, 1 missing. 



