1877 GUINEA-PIGS AND NETTLES 53 



June 6, 1877. 



I am very glad you sent me the extract from 

 Lamarck, for I had just been to the E.S., hunting 

 up several of the older authors to see whether any 

 mention had been made of the theory before Spencer 

 wrote. 



^Miile at Down I forgot my speculations about 

 inter-crossing, and, therefore, although I do not 

 think they are much worth, I send jou a copy of my 

 notes. The ideas are not clearly put — having been 

 jotted down a few years ago merely to preserve them 

 — ^but no doubt you will be able to understand them. 

 Do not trouble to return the MS. 



I had intended to ask you while at Down if you 

 happen to know whether stingiag nettles are endemic 

 plants in South America. The reason I should like 

 to know is, that last year it occurred to me that the 

 stiuging property probably has reference to some 

 widely distributed class of animals, and being told — 

 rightly or wrongly, I do not know — that ruminants 

 do not object to them, I tried whether my tame 

 rabbits would eat freshly plucked nettles. I found they 

 would not do so even when very hungry, but in the 

 same out-house with the rabbits there were confined 

 a number of guinea-pigs, and these always set upon 

 the nettles with great avidity. Their noses were 

 tremendously stung, however, so that between every 

 few nibbles they had to stop and scratch vigorously. 

 After this process had been gone through several 

 times, the guinea-pig would generally become furious, 

 and thinking apparently that its pain must have had 

 some more obvious cause than the nettles, would 



