46 AUTOBIOGRAPHY. [Oh. II. 



erroneous. Some of the adaptations displayed by climbing 

 plants are as beautiful as those of Orchids for ensuring cross- 

 fertilisation. 



My Variation of Animals and Plants under Domestication 

 was begun, as already stated, in the beginning of 1860, but was 

 not published until the beginning of 1868. It was a big book, 

 and cost me four years and two months' hard labour. It gives 

 all my observations and an immense number of facts collected 

 from various sources, about our domestic productions. In the 

 second volume the causes and laws of variation, inheritance, 

 &c, are discussed, as far as our present state of knowledge per- 

 mits. Towards the end of the work I give my well-abused 

 hypothesis of Pangenesis. An unverified hypothesis is of 

 little or no value ; but if any one should hereafter be led to 

 make observations by which some such hypothesis could be 

 established, I shall have done good service, as an astonishing 

 number of isolated facts can be thus connected together and 

 rendered intelligible. In 1875 a second and largely corrected 

 edition, which cost me a good deal of labour, was brought out. 



My Descent of Man was published in February 1871. As 

 soon as I had become, in the year 1837 or 1838, convinced that 

 species were mutable productions, I could not avoid the belief 

 that man must come under the same law. Accordingly I 

 collected notes on the subject for my own satisfaction, and not 

 for a long time with any intention of publishing. Although in 

 the Origin of Species the derivation of any particular species is 

 never discussed, yet I thought it best, in order that no honour- 

 able man should accuse me of concealing my views, to add that 

 by the work " light would be thrown on the origin of man and 

 his history." It would have been useless, and injurious to the 

 success of the book to have paraded, without giving any 

 evidence, my conviction with respect to his origin. 



But when I found that many naturalists fully accepted the 

 doctrine of the evolution of species, it seemed to me advisable 

 to work up such notes as I possessed, and to publish a special 

 treatise on the origin of man. I was the more glad to do so, as 

 it gave me an opportunity of fully discussing sexual selection 

 — a subject which had always greatly interested me. This 

 subject, and that of the variation of our domestic productions, 

 together with the causes and laws of variation, inheritance, and 

 the intercrossing of plants, are the sole subjects which I have 

 been able to write about in full, so as to use all the materials 

 which I have collected. The Descent of Man took me three 

 years to write, but then as usual some of this time was lost by 

 ill-health, and some was consumed by preparing new editions 



