1122 



MANUAL OF DETERMINATIVE BACTERIOLOGY 



Spherules with a diameter of about 0.5 terior or interior to the chromatin mass, 



micron, sometimes arranged in pairs, 

 sometimes with a thicker, crescentic, 

 stainable area of the periphery on one 

 side; parasitic within the nucleus, ex- 



which may be diminished in amount, but 

 does not disappear, nor is the parasitized 

 nucleus appreciably enlarged. 



Genus B. Drepanospira Petschenko. 

 (Arch. f. Protistenk., 22, 1911, 282.) 



Cell incurved in two spiral turns that arc not abrupt, one of the ends pointed, the 

 other a little rounded, no flagella, movement helicoid by means of all the body, no 

 cell division, endospores formed, regular spherical colonies formed by individuals at 

 certain stages of development. 



The type species is Drepanospira vmlleri Petschenko. 



1. Drepanospira miilleri Petschenko. 

 (Mullerina paramecii Petschenko, Cent, 

 f. Bakt., I Abt., Orig., 56, 1910, 90; 

 Petschenko, Arch. f. Protistenk., 22, 

 1911, 252; see also Kirby, in Calkins and 

 Sunmiers, Protozoa in Biological Re- 

 search, 1941, 1036.) Parasitic in the 

 cytoplasm of Paramecium caudatum. 



Developing from a group of curved 

 rods in the cytoplasm to a large, ellipsoi- 

 dal mass almost filling the body. Nu- 

 clear portion occupying part of the 

 cell. 



The author regards this genus as be- 

 longing in the family Spirillaceae be- 

 tween Spirosoma and Microspira. 



Genus C. Holospora Haffkine. 



(Ann. Inst. Past., 4, 1890, 151.) 



Genus established for bacterial parasites of the ciliate, Paramecium aurelia {■■ 

 Paramecium caudatum ?). 

 The type species is Holospora undulaia Haffkine. 



1. Holospora undulata Haffkine. 

 (Ann. Inst. Past., Paris, 4, 1890, 151.) 

 In the nucronucleus of the ciliate Para- 

 m,ecium aurelia (= P. caudatum?). 



Gradually tapered at ends; 1§, 2 and 

 2§ spiral turns; develops from a small, 

 fusiform body which grows and divides 

 transversely; brings about a great en- 

 largement of the micronucleus, which 

 becomes filled with the spirals (see 

 Drepanospira mulleri Petschenko). 



2. Holospora elegans Haffkine. (Haff- 

 kine, Ann. Inst. Past., Paris, 4, 1890, 

 154; see also Kirby, in Calkins and Sum- 

 iners. Protozoa in Biological Research, 

 New York, 1941, 1035.) In the micro- 

 nucleus of the ciliate, Paramecium 

 aurelia (= P. caudatum ?). 



Vegetative stage fusiform; elongated, 

 elliptical, nucleus-like body in some; 

 divides equatorially, budding at one end; 

 transformation into spore entails en- 

 largement, clear space separating mem- 

 brane at sides, spore pointed at ends. 



3. Holospora obtusa Haffkin. (Haff- 

 kine, Ann. Inst. Past., Paris, 4, 1890, 

 153; also see Fiveiskaja, Arch. f. Pro- 

 tistenk., 65, 1929, 276.) In the macro- 

 nucleus of the ciliate Paramecium au- 

 relia {= P. caudatum ?). 



Spores not spiralled and both ends are 

 rounded. Reproduction by fission, also 

 by formation of a bud at one of the ex- 

 tremities of the fusiform cell. Bodies 

 with rounded ends 12 to 30 microns long; 

 also spindle-shaped bodies with pointed 



