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question whether it was direct or indirect. Mr. West (Greenwich) 

 remarked that upon a tarred fence, nailed up to which were 

 some currant bushes, he always found the larvae of Abraxas 

 grossulariata, L., absolutely black, having no spots whatever, 

 but the imagines bred from these larvae were always typical. 

 Mr. Carrington said the question was whether animals had 

 the power during a single lifetime to adapt themselves to 

 their surroundings ; and if so, to what extent. One could not 

 understand why the moth was able to do so except from the 

 reason Mr. Weir suggested, that those who survived were 

 those that adapted themselves to their surroundings for 

 protective purposes. When he was at the Royal Aquarium, 

 he remembered some soles and plaice being brought there : 

 the soles harmonized with the colour of the sand at the 

 bottom of the tank in which they were kept ; but the plaice, 

 which were taken at the mouth of the Thames, were of 

 a delicate brown colour with very few spots, but being 

 placed in a tank having a gravel bottom with some white 

 stones among the gravel, within twelve hours the plaice were 

 covered with brilliant spots imitating the colour of the gravel. 

 This was not a solitary instance ; the experiment was carried 

 on for some considerable time, and in every case the fish 

 changed to the colour of the gravel at the bottom of the tank. 

 He could understand that the fish were more highly 

 organized than moths; but if one animal was capable of doing 

 this, he did not see why another should not. The fact that 

 Mr. West took absolutely black larvae of A, grossulariata 

 from a tarred fence, and also that black larvae of the same 

 species were every year found in the neighbourhood of 

 Newcastle-on-Tyne, seemed to suggest that the individual 

 had power to adapt its colour to its surroundings. Mr. Weir 

 said that the larger newt, if taken from a pond and placed 

 in a white basin for two or three hours, would lose its colour. 

 Mr. West (Streatham) said the small cuttlefish had power to 

 change its colour ; if placed in a white receptacle it would 

 turn almost the same colour, and he believed that the stickle- 

 back changed its colour in the same way. Mr. Step had 

 frequently noticed that if he took a toad from Wimbledon 

 Common and placed it in his garden, the soil of which was 

 much lighter than that of the Common, it would soon change 



