On the larval migration of some parasitic nematodes in the body of the host and its biological significance

Abstract

As Looss has shown, the larvæ of Ancylostoma can infect a suitable host by penetrating the healthy skin. If we place the infective material on the surface of the skin, after a short time we find the larvæ in the subcutaneous tissue. The same behaviour is shown by the filariform larvæ of Strongyloides siercoralis, which provide more convenient material for examination, because they can be collected very easily in pure culture and free from fluid by the special culture-method described by me (1924), the principle of which depends on the well-known fact that the filariform larvæ of Strongyloides and other nematode larvæ, accumulate in the form of white filaments of several millimetres in length (fig. 3), each consisting of thousands of individual larvæ, on little prominences in their vicinity, all being guided to similar places by the same sets of “tropisms” (Fülleborn, 1924).