To Thomas Stewardson   8 May 1860

Sir

I beg leave to acknowledge the receipt of your letter of April 16^th, in which you announce to me that I have been elected a Correspondent of the Academy of Natural Sciences of Philadelphia.¹ I assure that I fully appreciate & feel grateful for the great honour thus conferred on me, & I remain Sir | Your obliged & obed^t servant | Charles Darwin

To | D^r. Th. Stewardson | Corr. Secretary