ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 41 



New Species of Opercularia.* — B. Collin describes Opercularia 

 fanrei sp.n., which he found on the water-beetle Hydrophilus piceus. 

 The interesting retractile apparatus is homologous with the contractile 

 cord in Vortkella and Carchesium. There is a muscular bundle formed 

 by the convergence of basal myonemes, a more or less differentiated 

 plasmic axis, and an integumentary investment. But in Vortkella an 

 elongation of the aboral pole is continued within the stalk, whereas in 

 Opercularia an elongation of the body is inserted on the top of the stalk. 



Pathogenic Role of Balantidium coli.t — E. Brumpt submits ex- 

 perimental evidence showing that this well known parasite of man 

 (causing dysentery or colitis) is pathogenic in monkeys (Macacus cyno- 

 molgus). It may form a white lining along the whole large intestine. 

 The author transferred it from monkey to pig, and from pig to monkey. 

 He observed transverse fission, encystation of single individuals, and 

 encystation of two conjugating individuals. 



Symbiosis exhibited by a Ciliated Infusorian. \ — E. Faure- 

 Fremiet has studied one of the Trichodinidse, which lives in the 

 intestine of the mollusc Gyclostoma elegans. It was described long 

 ago (1858-61) by Claparede and Lachmann, as Trichodinopsis paradoxa, 

 and has been recently (190(3) studied in detail by R. Issel. 



"What previous observers have' taken to be vibratile cilia, are spirilla 

 living on the surface of the Infusorian. Moreover, the " enigmatical 

 body," described as enveloping the pharynx, is in the pharynx, and 

 consists of bacteria. There is an absolutely constant symbiosis of three 

 organisms : an ecto-parasitic spirillum, an internal symbiotic bacterium, 

 and the Ciliate. The. author notes that the genus Trichodinopsis must 

 be suppressed in favour of Trichodina. 



Tentacle-like Processes on Opalina dimidiata.§ — M. von Linden 

 describes the occurrence of processes, sometimes as long as the animal 

 itself, on specimens of Opalina from the frog. They bore a fringe of 

 fine cilia ; they were sometimes forked ; they persisted for at least 

 18 hours. Are they atypic locomotor structures, or pathological 

 altogether, or have they to do with division ? The observer inclines to 

 the third view. 



New Parasites of Dendrocceium.|| — E. Andre describes Ophryoglena 

 parasitica sp. n., an Infusorian living in the gut of the Planarian 

 Dendrocmlum lacteum. It differs very slightly from the free-living 

 species of the genus, and shows little traces of the effects of parasitism, 

 unless it be in the disappearance of the pharynx. 



Trypanosoma lewisi in Rat-louse. If — E. Rodenwaldt found no 

 Trypanosomes in lice (Hsematopinus spinulosus) which had sucked 

 uninfected rats. He does not believe in Crithidia hsematopini Patton, 

 a supposed parasite of the louse apart from the rat. But lice which 



* Arch. Zool. Exper., ii. (1909), Notes et Revue, No. 2, pp. xxi.-xxix. (2 figs.). 



t C.R. Soc. Biol. Paris, lxvii. (1909) pp. 103-5. 



j Tom. cit., pp. 113-4. 



§ Biol. Centralbl., xxix. (1909) pp. 648-50 (11 figs.). 



|| Revue Suisse Zool., xvii. (1909) pp. 273-80 (3 figs.). 



«|[ Centralbl. Bakt. Parasitenk., lii. (1909) pp. 30-42 (3 pis.). 



