My dear Sir

I thank you very sincerely for your kind & interesting letter.¹ It would be false in me to pretend that I care very much about my election to the Institut, but the sympathy of some few of my friends has gratified me deeply.—²

I am extremely glad to hear that you are going to publish a work on the more ancient fossil plants; & I thank you before-hand for the volume which you kindly say that you will send me.—³ I earnestly hope that you will give, at least incidentally, the results at which you have arrived with respect to the more recent Tertiary plants; for the close gradation of such forms seems to me a fact of paramount importance for the principle of evolution. Your cases are like those on the gradation in the genus Equus, recently discovered by Marsh in North America.—⁴

With the highest respect | I remain | Yours faithfully & obliged | Charles Darwin