728 SUMMARY OF CURRENT RESEARCHES RELATING TO 



budding. In other Acinetas, the author has observed isogamous con- 

 jugation, both total and partial. The divergence of Acinetas from the 

 stock of Peritricha probably occurred before total conjugation had 

 become the rule in the latter. 



Dimorphism of Ophryodendron.* — C. H. Martin, continuing his 

 observations on Acinetaria, publishes a paper on the dimorphism of 

 Ophryodendron, the only free-living Acinetarian in which the occurrence 

 of two different reproductive forms in the same species has been 

 observed. Ophryodendron is a somewhat aberrant Acinetarian fre- 

 quently found as an external parasite on Hydroids, and also, though 

 more rarely, on Crustaceans. It occurs under two remarkably different 

 forms : (a) a proboscidiform individual, characterised by the more or 

 less pyriform shape of the body, by the absence of a stalk (present, 

 however, in some forms), and by the presence of a long, very contractile 

 proboscis with rows of tentacles, {b) A vermiform individual charac- 

 terised by its elongated, cylindrical body, by the presence of a long 

 solid stalk which passes into the posterior end of the body, and by the 

 absence of a proboscis. The investigator describes both forms of 

 individual in 0. abietinum, and he also discusses the feeding 

 of Ophryodendron, with notes on nematocysts in some other Protozoa, 

 the external budding, and the ciliated buds. He finds that 0. 

 abietinum is a true ectoparasite of the hydroid to which it is attached, 

 and its contained nematocysts are derived from its host. This holds 

 good also for 0. sertvlarise. Ophryodendron is a true dimorphic form, 

 the proboscidiform individual giving rise by a process of external 

 budding to a vermiform individual of quite different structure. Both 

 forms of individual can give rise to ciliate embryos. The ciliate 

 embryos of the proboscidiform individuals develop on fixation into young 

 proboscidiform individuals. It is probable that the ciliate embryos of the 

 vermiform individuals also develop into proboscidiform .individuals. 



Hgemamoeba in a Bird, f — A. Laveran and A. Pettit describe 

 Hsemamtrba melopelise sp.n. in Melopelia leucoptera, a bird related to the 

 turtle-dove. It closely resembles H. majoris from a tomtit. 



New Trypanosome in a Bug4 — E. Chatton describes Leptomonas 

 agilis sp.n. in a bug, Harpactor iracundus (one of the Pentatomid 

 Hemiptera), living on Sisymbrium poly ceratum. 



Intestinal Parasites of Larval Tipulid.§ — L. Leger and 0. Duboscq 

 have found no less than four protist parasites, at least two of which are 

 new, in the intestine of a larva of Ptychoptera contaminate. They first 

 describe a Gregarine, which from the form of the epimerite, the frequent 

 occurrence of a nucleus in the protomerite, and other characters, they 

 place in the genus Pileocephalus as P. striatus sp. n. They describe at 

 length the effect of the parasite on the cells of the intestinal epithelium. 



* Quart. Journ. Micr. Sci., liii. (1909) pp. 629-64 (1 pi). 

 t C.E. Soc. Biol. Paris, lxvi. (1909) pp. 952-4 (13 figs.), 

 j Tom. cit., pp. 981-2. 

 § Bull. Acad. Roy. Belg., viii. (1909) pp. 885-902 (4 pis.). 



