RKVTEW — TnOPICAL MEDICINE, ETC. 143 



could not be the same species affecting mammals and man in Europe, notwithstanding Parasites— 

 the total absence of sti'uctural differences. Looss's recognition of the two species, G. sinensis conUimed 



and G. endemicns, had already been disputed, but he (Dr. Sambon) was inclined to accept 

 Looss's determinations, which he considered were founded on sound biological grounds. 



Amphistomum ivatsoni, a new trematodo of man, found in the jejunum of a negro in 

 German West Africa, and now assigned to the genus Gladorchis, is noticed, as are several new 

 Taenia — notably T. africana found in German Bast Africa. Sambon also mentions his 

 description of Sparganum baxteri from the same region, where it was found in the thigh of a 

 native, and alludes to two new human Linguatulidsd, L. serrata and Porocephalus arniillatus. 

 He believes that five specimens of cylindrical linguatulid from the liver of African natives 

 were really nymphal forms of P. armillatus, which is a parasite of the West African python. 

 P. armillatus has never more than 22 rings, while P. moniliformis has from 28 to 30. 

 He mentions various animals, including Ugandese monkeys, in which these nymphal 

 forms have been found. The adult form occurs in African pythons and in the nose-horned 

 viper, and hence its distribution should be coterminous with that of these ophidia, an area 

 corresponding with that of the chimpanzee. This being so, it possibly occurs in a portion 

 of the Bahr-Bl-Ghazal Province of the Anglo-Egyptian Sudan. 



Sambon then proceeds to discuss bionomics and pathogeny, and a portion of this part of 

 the paper may well be quoted : — 



With regard to A. lumbricoides, the common lumbricoid worm of man, the general belief was that it reached 

 the small intestines directly through the stomach, and, indeed, immature forms of this para.site had been passed 

 by man. But he would point out that the larva of A. lunihricoiclcs, like the larvae of the above-mentioned species, 

 was also provided with a perforatiug tooth which must obviously serve the same purpose, and that although we 

 now belieVed that the development of this parasite occurred entirely within the one host, very competent 

 observers, such as Leuckart, Brown and Vou Linstow, had suggested that the larval stage might be spent in an 

 intermediary host. 



The Giialhoslomidie were again nematodes, the adult forms of which occurred in the stomach of vertebrates. 

 In an earlier developmental stage they were usually found in cysts beneath the mucosa. One species, 

 6fiuUJwstomam sianiensc, had been found by Deuntzer in man in rounded nodules beneath the skin. 



In the case of Trichindla spiralis, the adult forms seemed likewise to enter the lumen of the small 

 intestines for the sole purpose of fertilisation ; the males usually died shortly after copulation. The whole period 

 of growth was spent in a different part of the body, namely, in the connective tissue between the fibres of 

 the striated muscles. The larvse, extruded by the female worms into the interior of Lieberkuhn's glands, were 

 carried into the circulating blood through the chyle vessels and thus reached the muscul.ature. 



Many nematodes entered their host in the egg or early larval stage, and although they invariably changed 

 their anatomical habitat in the course of development, yet they did not leave their host, but completed within its 

 body their entire life-cycle. Their ova never developed by their side within the same host, but must necessarily 

 reach a fresh host after a shorter or longer period in the outer world. T. spiralis entered the intestine of a fi'esh 

 host at the end of the larval period ; its young did not leave this host, but they migrated from the intestine to 

 the musculature, and there developed until they reached a certain stage of growth beyond which they could not go 

 unless their host were devoured by some other suitable animal. Thus, although all stages occurred within the same 

 host, the life-history of the individual par.asite w.as distributed between two hosts, which might belong to the same 

 species (rats alone) or to different genera (rats and swine). In other eases, as in the majority of cestode infections, 

 they found the larval or somatic stage in one host, the adult or intestinal stage in another host, usually belonging 

 to widely sundered zoological groups. It was evident, therefore, that the life-history of each species of parasite, 

 whether spent entirely in one host or distributed between two or more hosts, consisted of a larval, somatic stage, 

 alternating with an adult stage located either within the intestines or in other parts (bile ducts, bronchial tubes, 

 trachea, nasal fossje) leading to the exterior. Occasionally the adult form inhabited the subcutis ; iu such cases, as 

 iu Draeitneuhis mcdiiioisis, it perforated the skiu .at the time of parturition. Unfortunately, little or nothing was 

 known with regard to the larval stages of most entozoa. 



Time would not allow him to give more examples, or describe more fully the life-history of the parasites he 

 had mentioned, but he hoped he had said enough to prove that an accurate and minute knowledge of the life- 

 history of each species was indispensable to fully understand its pathogeny. Before accepting the theories of the 

 chemist, who pounded worms iu a mortar, he would like to hear the biologist. He believed that the migrations 

 of the larval forms had not been taken sutficiently into account. Trichinosis was one of the few diseases in which 

 the symptoms had been correctly ascribed to the agency of the larval forms. Now we should probably have to 

 change our views with regard to the pathogeny of ankylostomiasis. The anaimic conditions of persons harbouring 

 Ayi-hi/lostoiiiuiii duodenali: could not be entirely ascribed to the direct abstraction of Ijlood, since it had been 

 practically demonstr.atod that the parasite was not a true blood-sucker. The anaamia of ankylostomiasis, like that 

 of trichinosis might probably find its explanation, partly at least, in the actual migrations of the larvfe through 

 the viscera and through the intestinal walls. The migrations of the comparatively large linguatulid nymphae at 

 the end of their encysted stage exemplified in a striking manner the nature of the process he wished to draw 

 attention to. Writing on the pathogeny of Porocephalus armillatus, certain authors had expressed the oijiuion 

 that this species is probably harmless to its hosts. He doubted whether such authors had ever set down the pen 

 to handle the autopsy knife. 



The paper is concluded by a few notes on the transmission of secondary infections by 

 helminths. 



