From H. B. Brady   22 October 1871

My dear Sir,

I think Prof. Shaler’s view rê the rattle-snake—is rather, that the rattle instead of alarming the small birds on which the snake preys, in reality attracts them—¹ Birds feeding on the Cicada suppose the sound of the snake to proceed from an insect and are thus drawn within range.

I shall have to write to Prof^r Shaler in a day or two on some other matters & will get on paper such further particulars as I can— He is a shrewd observer & I should have much confidence in any details given on the strength of his own observations. Whilst with him my attention was more turned to some palæontological matters bearing on my own special line of study & conversations on topics of more general interest were a good deal en parenthêse as it were.

The subject is one of importance & as comparatively few scientific men are really familiar with rattlesnakes in their native haunts it is an object to obtain the experience of those who are.

Yours, dear Sir, | very faithfully | Henry B. Brady.

Charles Darwin Esq | &c. &c. &c.