[4][5] Sherborn developed a passionate interest in geology and paleontology and in 1883 he was asked by geologist Thomas Rupert Jones to help illustrate and complete some papers he was writing on fossil Foraminifera.
In this new role he had the opportunity to collaborate with Arthur Smith Woodward, an expert on fossil fish and another influential colleague in Sherborn's career.
[1] Encouraged by the success of his first bibliography, Sherborn began to contemplate a much more ambitious project—the indexing of every living and extinct animal species discovered since 1758.
During the day he continued to prepare fossils in the museum while at night he would work at home, methodically going through thousands of books and journals, recording onto slips of paper every species name he came across.
[8] He was required to sort through Owen's papers, which had been left, in piles twelve feet high, in a cowshed exposed to rats and to the elements.
Despite Sherborn's great pleasure in the task, the effort involved caused a breakdown in his health that left him nearly incapacitated for three years.
Nevertheless, Sherborn succeeded with the enormous task, sorting and distributing hundreds of scientific papers and thousands of pages of correspondence.