My dear Sir

It was very good of you to give up so much of your time to write to me your last interesting letter.² The evidence seems good about the tameness of the alpine Butterflies, & the fact seems to me very surprising; for each butterfly can hardly have acquired its experience during its own short life.— Will you be so good as to thank M. Humbert for his note, which I have been glad to read.³ I formerly received from a man, not a naturalist staying at Cannes, a similar account, but doubted about believing it.⁴ The case, however, does not answer my query, viz whether Butterflies are attracted by bright colours, independently of the supposed presence of nectar.

I must own that I have great difficulty in believing that any temporary condition of the parents can affect the offspring. If it last long enough to affect the health or structure of the parents, I can quite believe the offspring would be modified. But how mysterious a subject is that of generation! Although my hypothesis of pangenesis has been reviled on all sides,⁵ yet I must still look at generation under this point of which; & it makes me very averse to believe in an emotion having any effect on the offspring.

Allow me to add one word about blushing & shyness: I intended only to say that the habit was primordially acquired by attention to the face; & not that each shy man now attended to his personal appearance.—⁶

With sincere thanks, believe me, yours very faithfully | Ch. Darwin