Some British Freshwater Larval Trematodes with Contributions to their Life Histories

Abstract

Although, in the early part of the nineteenth century, a considerable amount of work on larval trematodes was done on the continent by von Siebold (1835), de Fillippi (1855) and La Valette (1855), so far as I know, no similar work was undertaken in this country. It was not until 1880, when a great controversy raged round the intermediate host of the liver fluke, that any interest was aroused. This culminated in 1883 with the publication, by Thomas, of the life history. Thomas also discovered that Limnaea peregra was infected with cercariae different from those of the liver fluke. Since that time the interest has lapsed, and, excluding a description of two cercariae by Hesse (1923), I do not know of any published records of work on freshwater larval trematodes of this country. On the other hand, work on the continent and in America has increased, and although our knowledge of the life histories of trematodes is still in its infancy, a considerable number of continental larval forms have been found and described. However, Lebour (1905) commenced a study of marine larval trematodes and together with Nicoll (1906) attempted to establish life histories.