

i86o.] LYELL'S CRITICISMS. 337 



marine algae. I have said what I can in defence, but yours 

 is a good line of attack. We should, however, always re- 

 member that no change will ever be effected till a variation 

 in the habits or structure or of both chance to occur in the 

 right direction, so as to give the organism in question an 

 advantage over other already established occupants of land 

 or water, and this may be in any particular case indefinitely 

 long. I am very glad you will read my dogs MS., for it will 

 be important to me to see what you think of the balance of 

 evidence. After long pondering on a subject it is often 

 hard to judge. With hearty thanks for your most interesting 

 letter. Farewell. 



My dear old master, 



C. DARWIN. 



C. Darwin to J. D. Hooker. 



Down, September 2nd [1860]. 



MY DEAR HOOKER, I am astounded at your news re- 

 ceived this morning. I am become such an old fogy that I 

 am amazed at your spirit. For God's sake do not go and get 

 your throat cut. Bless my soul, I think you must be a little 

 insane. I must confess it will be a most interesting tour ; 

 and, if you get to the top of Lebanon, I suppose extremely 

 interesting you ought to collect any beetles under stones 

 there ; but the Entomologists are such slow coaches. I 

 dare say no result could be made out of them. [They] have 

 never worked the Alpines of Britain. 



If you come acrdss any Brine lakes, do attend to their 

 minute flora and fauna ; I have often been surprised how 

 little this has been attended to. 



I have had a long letter from Lyell, who starts ingenious 

 difficulties opposed to Natural Selection, because it has not 

 done more than it has. This is very good, as it shows that 

 he has thoroughly mastered the subject ; and shows he is in 



VOL. II. z 



