To G. R. Gray [February–March 1841]
12 Up. Gower St
My dear Sir
Will you oblige me by looking over the proof of the index, & just marking any error you may observe.— It is such an interminable job to compare every name with text & your memory probably is far more accurate than mine.—
I will send proof of your Errata, soon—
If any of the Specimens of Birds are at hand the Bearer may as well bring some back
Yours most sincerely | Chas. Darwin
Sends proof of index of final number of Birds for checking.