392 POPULAR SCIENCE MONTHLY. 



to the more important parts of the subject. He said that he had 

 much more written out, but time failed. After conversation with 

 others and more reflection, I must confess that as an exposition of the 

 doctrine the lecture seems to me an entire failure. I thank God I 

 did not think so when I saw Huxley ; for he spoke so kindly and mag- 

 nificently of me, that I could hardly have endured to say what I now 

 think. He gave no just idea of Natural Selection. I have always 

 looked at the doctrine of Natural Selection as an hypothesis, which, 

 if it explained several large classes of facts, would deserve to be ranked 

 as a theory deserving acceptance; and this, of course, is my own 

 opinion. But, as Huxley has never alluded to my explanation of 

 classification, morphology, embryology, etc., I thought he was thor- 

 oughly dissatisfied with all this part of my book. But to my joy I 

 find it is not so, and that he agrees with my manner of looking at the 

 subject; only that he rates higher than I do the necessity of Natural 

 Selection being shown to be a vera causa always in action. He tells 

 me he is writing a long review in the Westminster. It was really 

 provoking how he wasted time over the idea of a' species as exemplified 

 in the horse, and over Sir J. Hall's old experiment on marble. 

 Murchison was very civil to me over my book after the lecture, in 

 which he was disappointed. I have quite made up my mind to a 

 savage onslaught; but with Lyell, you, and Huxley, I feel confident 

 we are right, and in the long run shall prevail. I do not think Asa 

 Gray has quite done you justice in the beginning of the review of me. 

 The review seemed to me very good, but I read it very hastily. 



To J. D. Hookek. 



Down, Nov. 20th [1862]. 

 Your last letter has interested me to an extraordinary degree, and 

 your truly parsonic advice, 'some other wise and discreet person,' 

 etc., etc., amused us not a little. I will put a concrete case to show 

 what I think A. Gray believes about crossing and what I believe. If 

 1,000 pigeons were bred together in a cage for 10,000 years their 

 number not being allowed to increase by chance killing, then from 

 mutual intercrossing no varieties would arise; but, if each pigeon 

 were a self-fertilising hermaphrodite, a multitude of varieties would 

 arise. This, I believe, is the common effect of crossing, viz., the 

 obliteration of incipient varieties. I do not deny that when two 

 marked varieties have been produced, their crossing will produce a 

 third or more intermediate varieties. Possibly, or probably, with 

 domestic varieties, with a strong tendency to vary, the act of crossing 

 tends to give rise to new characters; and thus a third or more races, 

 not strictly intermediate, may be produced. But there is heavy evi- 



