This investigation was carried out for two reasons, firstly that there would appear to be no detailed description of the changes in the leaf structure in Plantago lanceolata L. under the influence of parasitization by Anguillulina dipsaci (Kühn) Gerv. & v. Ben., and secondly that material for study was readily available.

Our knowledge of the range of intermediate hosts of which Syngamus trachea can take advantage is increasing. Recent observations have shown that the centipede, Scolopendra sp., the leatherjacket, Tipula sp., and the spring tail, Sminthurus viridis may all act as vectors. In each case the larvae had migrated from the gut into the surrounding tissues where they had settled down. All these Arthropods have been found naturally infected on a plot of land known to be carrying a heavy burden of gapes.

In 1937 a short paragraph by Whitlock appeared in the Journal of Parasitology commenting on the fact that there appeared to be a sexual difference in the degree of infection with Syngamus trachea of some Hungarian partridges which were being confined at the Michigan State Game Farm. Of 34 infected birds that he examined, 32 were females. He puts forward the suggestion that the strain of egg laying had lowered the vitality of the females to such an extent as to allow of the establishment of the parasite. We must assume therefore that all these birds were fully adult and that they were examined in the spring or early summer.

The activity, infectivity and fat content of ageing infective larvae of Ancylostoma caninum were investigated at regular intervals.

The reduction in activity and fat content was found to occur at a similar rate.

On farms in the Border Counties of Scotland, the sheep enterprise represents the chief line of production in both upland and lowland districts. Stocks of breeding ewes are run on practically all low-ground farms in the area, and these mainly consist of half-bred ewes (Border Leicester × Cheviot) which are mated with Oxford or Suffolk rams. The larger farms carry, in addition, their own flocks of Cheviot ewes for the production of half-bred ewe lambs for stock purposes. The number of cattle maintained on the pastures is comparatively small, though it is well recognised by farmers that an increase in their numbers would be to the advantage of the sheep.

Until comparatively recently, the greater part of research work in helminthology progressed along three main lines, investigation into the life histories of parasitic helminths, the study of their morphology as well as an empirical investigation into the efficiency or otherwise of different substances as anthelmintics. Research into the physiology of these animals was only rarely attempted and even then was only very casual and never by any means thorough. In recent years, however, there has been a gradual change over, and increased attention has been paid to their physiology, both from a purely scientific and also an applied standpoint. Early work on anthelmintics was concerned only with the discovery of substances which would expel the worms from their hosts and could be used empirically. This attitude has of recent years, given place to a more scientific approach in which investigations into physiological processes have been undertaken in the hope that knowledge gained might show some method of rendering the worms more susceptible to anthelmintics, or alternatively, indicate new anthelmintics more lethal to them and less harmful to the hosts.

The first report of a species of Strongyloides parasitic in cats appears to be that by Chandler (1925 and 1925a). Sandground (1925b) found that cats could be infected with Strongyloides stercoralis from the dog but infections were light and were retained for short periods only. Later (1928) he found that cats had a slightly greater susceptibility to the human strain of S. stercoralis than dogs.