Leonard Jenyns (1800–1893) and the identification of specimens

One of Darwin's fish specimens (Seriolychthis bipinnulata) first described by Leonard Jenyns.

Darwin’s first months back in England were spent with Henslow in Cambridge, sorting through his vast collections of specimens and arranging for them to be identified and researched by a number of different specialists.  One problem was the disposal of the large number of fish specimens, as no established experts were immediately available to work on them.  Leonard Jenyns, Henslow’s brother-in-law, had known Darwin since he was an undergraduate and despite the difference in their ages (Jenyns was a few years older), their shared passion for natural history had drawn them together. Jenyns had been offered the place on the Beagle before Darwin, but had a young family and had been forced to turn it down. At Darwin’s request, and with little previous experience, Jenyns took on the challenge of identifying the Beagle fish. This task was to be the most rigorous and exacting scientific work that Jenyns would ever undertake and culminated in the Fishes of the Zoology of the Voyage of the Beagle published between 1840 and 1842. Jenyns later joked that just the mention of Darwin’s name conjured up a fishy smell.