To Christian Gottfried Ehrenberg 22 July [1866?]1
Down. | Bromley. | Kent. S.E.
Dear & honoured Sir
I beg leave to return you my sincere thanks for your two papers on the Tuff of Mexico & on the “Organisations-Präparate”, with its beautiful illustrations, shewing for what a wonderful length of time your method has preserved the specimens.2
I feel sincerely honoured by your kind remembrance of me & for the valuable assistance which many years ago you were so good as to afford me3
With the most sincere respect | I remain dear Sir | yours truly obliged | Ch. Darwin
Thanks CGE for two papers and for his assistance of many years ago.