ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 313 



eichhorni var. viride, Raphidiophrys glomerata sp. n., Acanthocystis longi- 

 scta sp. n. and A. hulibunda sp. n. 



Multiplication of Herpetomonas.* — Louis Leger finds that H.jacu- 

 lum sp. n., an abundant flagellate parasite in the midgut of Nepa cinerea, 

 occurs in two forms conuected by intermediate stages. Most abundant 

 are the monad-like forms, with a loug flagellum, and very mobile, multi- 

 plying by longitudinal fission. But there are also gregarine-like forms 

 of larger size, which occur fixed in rows to the epithelial cells, and also 

 multiplying by longitudinal fission. The existence of gregarino-liko 

 forms in a typical Flagellate seems to the author a strong argument in 

 favour of the origin of Sporozoa from a Flagellate stock. 



New Sporozoon.f — L. Brasil gives a preliminary account of Joyeux- 

 ella toxoides g. et sp. n. from the intestinal epithelium of the Pecti- 

 narian Lagis Jcoreni Malmgren. It shows certain resemblances to other 

 Sporozoon parasites of Annelids, especially to Gonospora longissima, 

 Toxosporidium, and Selenidium ; it is however distinct, and must remain 

 at present unattached. 



Action of Human Serum on Trypanosoma Brucei.J — A. Laveran 

 has found that human serum injected into rats and mice infected with 

 Nagana or Tsetse-fly disease destroys the parasites (Trypanosoma brucei) 

 in the blood. But there are evidently corners of the organism where the 

 parasites are able to resist with success the microbicidal influence of the 

 serum. Thence they reappear with disappointing persistence. The 

 serum seems also to be in a feeble degree preventive, and Laveran pro- 

 poses to pursue the inquiry as to possible immunisation of animals. It 

 is probable that the influence of human serum on Trypanosoma brucei is 

 associated with the immunity of man to Tsetse-fly disease, but this in- 

 terpretation remains incomplete until there is some understanding of the 

 defensive process in the human body against this formidable parasite. 



Protozoa of the Volga-Plankton.§ — W. Zykoff records about 75 

 species of Protozoa from the Volga at Saratow, including Tetraedrophrya 

 planctonica g. et sp. n., a new suctorial form. As autopotamic Pinacio- 

 phora fluviatilis may be reckoned ; various species of Difflugia (except 

 D. planctonica), Vorticella, Suctoria, and Amoebidaa may be regarded as 

 tychopotamic, and characteristic of the potamo-plankton of the Volga is 

 the occurrence of Heliozoa in considerable numbers, e.g. Actinophrys sol, 

 Actinosphserium eichhornii, Acanthocystis myriospina, and Bhaphidiophrys 

 elegans. 



* Comptps Kendus, cxxxiv. (1902) pp. 781-4 (7 figs.). 



t Arch. Zool. Exper., x. (1901) Notes et Revue, pp. v.-vii. (13 figs.). 



X Oomptes Rendus, cxxxiv. (1902) pp. 735-9. 



§ Zool. Anzeig , xxv. (1902) pp. 177-80. 



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