110 GEOEGE JOHN ROMANES i8si 



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 reasoning, 

 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 Gr. H. Lewes hinted at the same funda- 

 mental idea, viz. that there is a struggle going on 

 ivithin every organism between the organic molecules, 

 the cells, and the organs. I tliinh that his basis is 

 that every cell which best performs its function is as 

 a consequence at the same time best nourished and 

 best propagates its kind. The book does not touch on 

 mental phenomena, but there is much discussion on 

 rudimentary or atrophied parts, to which subject you 

 formerly attended. Now if you would like to read this 

 book, I will send it after Frank has glanced at it, for 

 I do not think he will have time to read it with care. 

 If you read it and are struck with it (but I may be 

 wholly mistaken about its value), you would do a 

 pubhc service by analysing and criticising it in 

 ' Nature.' Dr. Eoux makes, I think, a gigantic over- 

 sight in never considering plants ; these would 

 simplify the problem for him. 



Fourthly, I do not know whether you will discuss 

 in your book on the ' Mind of Animals ' any of the 

 more complex and wonderful instincts. It is un- 

 satisfactory work, as there can be no fossilised in- 

 stincts, and the sole guide is their state in other 

 members of the same order and mere probability. But 



