312 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Notes on Anchylostomum.* — Gino Pieri finds that Anchylostomum 

 duodenale may infest clogs, may attain in these hosts to the adult repro- 

 ductive stage, and may pass into the intestine by oral infection as well 

 as cutaneously. 



Biology of Filaria bancrofti, Cobbold.f — X. Taniguchi records 

 from the island of Kiushiu frequent cases of swelling of lymphatic 

 glands, elephantiasis, and chyluria, in which Filaria embryos are present 

 in the blood mostly during night, but in daytime also. The embryos 

 vary from • 16 to ' 31 mm. in length ; in breadth they measure between 

 • 04 and ' 08 mm. They are for the most part carried by Culex pipiens, 

 rarely by Anopheles, and not by fleas or lice. As soon as the embryos 

 enter the stomach of Culex, they are in some cases digested ; in others, 

 within 21 hours, they reach the thorax, and there commence metamor- 

 phosis. In from 11 to 14 days they arrive at the labium of the mosquito, 

 and on the stinging of the human body are liberated into the wound. 

 They are possibly also transmitted by being deposited upon fruits when 

 these are sucked by Culex, and subsequently transferred to an unsound 

 human stomach. No explanation of their appearance mostly by night 

 has been found. It is noted that Rontgen rays disturb the appearances 

 of the embryos, and lessen their lively movements. 



Platyhelminthes . 



Pearl-Producing Cestode.J — L. Gr. Seurat finds that in pearl- 

 oysters {Margaritifera margaritifera var. cummingi, Reeve) from the 

 Gambier lagoons (South Pacific) the production of pearls is due to the 

 scolex of a Cestode referable to the genus Tylocephalum Linton. In 

 latero-dorsal cysts on the body and mantle of the oyster true pearls are 

 formed around a nucleus, which is demonstrably a scolex. The life- 

 history seems to be continued in the ray (Aetobatis narinari), for in the 

 spiral intestine of this fish small tapeworms were found, which the author 

 regards as the adult forms of the pearl parasite (T. margaritiferm sp. n.). 

 The rays appear to have a preference for those pearl oysters whose shells 

 are riddled by the sponge Clione. 



The genus Tylocephalum is represented by another species in the 

 spiral valve of Rhinoptera auadriloba. 



Taenia acanthorhyncha, Wedl.S — Al. Mrazek describes this remark- 

 able tapeworm from Colymbus fluviatilis. The vagina remains blind ; a 

 new secondary female genital opening is formed ; there is a free com- 

 munication between the receptaculum seminis in one proglottis and 

 that of the succeeding proglottis. This is a quite unique feature. 

 Kowalevsky's Tatria biremis is a closely allied species. 



Life-History of Cyathocephalus truncatus.|| — R. Wolf finds that 

 this Bothriocephalid, adult in fresh-water fishes, has its larval form in 

 Gammarus. The larva differs but little from the sexually mature 



* Atti Rend. R. Accad. Lincei Roma, xiv. (1905) pp. 727-30. 

 t Chiusei Iho, West Japan, 1905. See also Centralbl. Bakt. Parasit., xxxvii. 

 (1906) p. 752. % Comptes Rendus, cxlii. (1906) pp. 801-3. 



§ SB. k Bohm. Ges. Wiss., vii. (1905) pp. 1-24 (2 pis. 7 figs.). 

 || Zool. Anzeig., xxx. (1906) pp. 37-45 (5 figs.) 



