From A. R. Wallace   30 January 1869

Dear Darwin

Will you tell me where are Fleming Jenkyn’s arguments on importance of single variations.¹ Because I at present hold most strongly the contrary opinion, that it is the individual differences or general variability of species that enables them to become modified and adapted to new conditions.

Variations or “sports” may be important in modifying an animal in one direction, as in colour for instance, but how it can possibly work in changes requiring co-ordination of many parts, as in Orchids for example, I cannot conceive. And as all the more important structural modifications of animals & plants imply much coordination, it appears to me that the chances are millions to one against individual variations ever coinciding so as to render the required modification possible.

However let me read first what has convinced you.

You may tell Mrs. Darwin that I have now a daughter.²

Give my kind regards to her & all your family.

Very truly yours | Alfred R. Wallace—