Most of the 17 letters are in his hand, though one, sent at a time when he was unwell, is in that of his wife, Emma.
The German cataloguer provided brief descriptions but also added references to the Darwin Correspondence Project, whose admirable website has information in English.
There, the earliest letter of the group, No. 3660F of August 1862, is summarised as one that thanks Hildebrand for his offer to translate Darwin’s work on Orchids… into German, but tells him that HG Bronn had completed the translation before his recent death. Darwin also notes that he has not yet received Hildebrand’s 1861 work on the distribution of coniferous trees.
The illustration above is a reminder of how simple postal addresses could be in past times. Dr Hildebrand lived in ‘…Bonn, Prussia’.