The only account we have of this species of nematode, which is apparently parasitic in the bark of mahogany trees in Barbados, British West Indies, is that given by Cobb (1920). The material forming the basis of his investigations consisted of specimens preserved in formalin which had been sent to him from the Department of Agriculture, Barbados. His description of the adult worms, while being very detailed in certain particulars, gives little information in regard to other anatomical features. In addition, the drawings illustrating his paper show only two views of the head region and the male tail in ventral and lateral aspect. During the past twelve months the writer has had an opportunity of making some observations on this species. A piece of diseased mahogany bark was received in April, 1936 from the Director of the Imperial Mycological Institute, Kew, to whom it had been sent from the Department of Agriculture, Barbados. The bark and scrapings from it were in a preserving fluid of unknown composition and in the sediment at the bottom of the jar numbers of adult worms of both sexes were present. Several of these were picked out, washed in water and transferred to weak glycerine. The capsule containing them was set aside for the glycerine to become concentrated and the worms were finally mounted in this medium.

In the investigation of plant material infested with parasitic and related nematodes various methods are available. One often has recourse to the teasing apart of affected tissues in water with the liberation of the contained organisms or the latter may be obtained by soaking the material in a Baermann funnel. It is frequently desirable, however, to determine the actual presence and location of nematodes in the host tissues without recourse to teasing and for this purpose some appropriate method of staining is necessary such that the nematodes are suitably coloured whilst the tissues of the host are coloured but little or not at all and thus permit the passage of light after the usual processes of dehydration and clearing have been carried out.

1. The results of post-mortem examinations of 590 dogs and 185 cats in Shanghai are reported.

2. 88% of the dogs and 97% of the cats were infected with one or more species of helminthic parasite. The cats tended to harbour a larger number of species per animal than the dogs.

3. Infections with trematodes were very common, especially Clonorchis sinensis which was present in 79% of the cats.

4. There was a comparatively low incidence of infection with Ancylostoma caninum.

5. Prohemistomum industrium, and Echinostoma ilocanum, rare parasites of the dog, occurred.

6. The following parasites are recorded in their hosts for the first time in China.

1. Chlamydonema praeputialis in the dog.

2. Cylicospirura subaequalis in the cat.

3. Metorchis albidus as a natural infection in the dog.

From time to time attempts have been made to control the spread of sclerostome larvae by treating the manure before use on the pastures or by mechanical means such as ploughing the land to bury the larvae. Various chemicals have been used, including artificial manures and animal waste products. Lucker (1936) buried larvae at varying depths in soils of different quality and measured the percentage that appeared on the surface during periods up to six weeks. Clay soils were almost a complete barrier to vertical migration whereas sandy soils and coarse sand permitted migration, during a period of 3–8 weeks, of appreciable numbers when buried 1–6 inches. He suggests from this evidence that ploughing the land would bury the larvae and therefore reduce the number of infective larvae available to the stock. It would seem to the writer, however, that there is a fallacy in this argument. Ploughing the land would turn the soil over but, even if a plough press were used, many fissures would be left which might form an easier channel for migration to the surface. Infective larvae readily accomplish horizontal migration and the possibility of lateral migration along the overturned turf and up the fissures must not be overlooked. The action of frost and the presence of roots in the overturned sod would possibly be other factors in encouraging vertical migration, not to mention the subsequent preparation of the land required before seeding down again for permanent pasture.

In the routine examination of stray dogs in a country area near Shanghai, a large percentage were found to be infected with Dirofilaria immitis. The microfilariae were easily found in blood films stained with Leishman's or Giemsa's stain. In some cases only a moderately heavy infection was found, but in some hyper-infection was present. (See fig.)

It is a rather surprising fact, that very little information is available regarding the numbers of different species of parasites normally present in apparently healthy lambs, and the frequency of occurrence of these parasites. Often all that can be said is that one species is fairly common, occurring in large numbers, while another is of infrequent occurrence, being present in comparatively small numbers. Without exact data it would be impossible for one to determine with any degree of certainty the importance of any parasite as an agent responsible for the deterioration of stock, nor would one be justified in ascribing the “low” or poor condition of a lamb to any particular worm present in its gut.