In late 1879, Rolleston, the Linacre professor of anatomy and physiology, appointed Thomas junior demonstrator in human and comparative anatomy at the Royal Agricultural Society to investigate the sheep liver fluke ( " Fasciola hepatica " ), a parasite flatworm that in the winter of 1879 80 had caused the loss of some three million sheep in England.
12.
His scientific accomplishments included ( in 1851 ) collaborating with Theodor Bilharz on the first description of the blood-fluke " Schistosoma haematobium ", ( in 1853 ) the elucidation of the life cycle of the tapeworm " Echinococcus granulosus ", ( in 1854 ) the suggestion that the cercariae of the fluke " Fasciola hepatica " were the infective stage which passed from the invertebrate to the vertebrate host, and ( in 1856 ) the discovery of parthenogenesis in insects.
