i88i.] 'WORMS.' 4J9 



they do not understand, but this was omitted on the advice 

 of a friend, and curiously enough a friend whose combative- 

 ness in the good cause my father had occasionally curbed.] 



C. Darwin to G. J. Romanes. 



Down, April 16, 188 1. 



My dear Romanes, — My MS. on 'Worms' has been sent 

 to the printers, so I am going to amuse myself by scribbling 

 to you on a few points ; but you must not waste your time in 

 answering at any length this scribble. 



Firstly, your letter on intelligence was very useful to me 

 and I tore up and re-wrote what I sent to you. I have not 

 attempted to define intelligence ; but have quoted your 

 remarks on experience, and have shown how far they apply 

 to worms. It seems to me that they must be said to work 

 with some intelligence, anyhow they are not guided by a 

 blind instinct. 



Secondly, I was greatly interested by the abstract in 

 ' Nature ' of your work on Echinoderms,* the complexity with 

 simplicity, and with such curious co-ordination of the nervous 

 system is marvellous ; and you showed me before what splen- 

 did gymnastic feats they can perform. 



Thirdly, Dr. Roux has sent me a book just published by 

 him: ' Der Kampf der Theile,' &c , 1881 (240 pages in 

 length). 



He is manifestly a well-read physiologist and pathologist, 

 and from his position a good anatomist. It is full of reason- 

 ing, and this in German is very difficult to me, so that I have 

 only skimmed through each page ; here and there reading 

 with a little more care. As far as I can imperfectly judge, it 

 is the most important book on Evolution, which has appeared 

 for some time. I believe that G. H. Lewes hinted at the 

 same fundamental idea, viz. that there is a struggle going on 

 within every organism between the organic molecules, the 



* " On the locomotor system of Echinoderms," by G. J. Romanes and 

 J. Cossar Ewart. 'Philosophical Transactions,' 1SS1, p. 829. 



