NOTES ON SOME PARASITIC PROTISTS. 137 
17. Scuewiakorr, W.—* Uber einen neuen bakterienahnlichen Organismus 
des Siisswassers,” ‘ Verhandl. naturhist.-med. vereins Heidelberg,’ 
1893, N.F., 5, p. 44. 
18, SWELLENGREPEL, N. H.—‘ Zur Kenntnis der cytologie von Bacillus 
maximus buccalis (Miller),’ ‘CB. Bakt. Parasitenk.,’ ii Abt., xvi, 
1906, pp. 617 and 673. 
19. SWELLENGREBEL, N. H.—“Sur la cytologie comparée des Spirochétes 
et. des Spirilles,”’ ‘Ann. Inst. Pasteur,’ xxi, 1907, pp. 448 and 562. 
20. Vespowsky, F.-—‘‘ Bemerkungen iiber den Bau und Entwickelung der 
Bakterien,” ‘CB. Bakt. Parasitenk.,’ ii Abt., vi, 1900, p. 577. 
Pals “Uber den Kern der Bakterien und seine Teilung,” loc. cit., 
xi, 1904, p. 481. 
22. Zetrnow, W.—“ Uber den Bau der grossen Spirillen,” ‘Zeitschr. f. 
Hygiene,’ xxiv, 1897, p. 72. 
EXPLANATION OF PLATE 6, 
Illustrating Mr. C. Clifford Dobell’s paper on “ Notes on 
some Parasitic Protists.” 
[Figs. 1—8 are drawn from life, under the Zeiss 2°5 mm. (apert. 1:25) 
water immersion objective, compensating ocular 12. The remainder are from 
permanent preparations stained by Giemsa’s method. Figs. 9—19 alcohol 
fixation, and Figs. 20—23 formalin fixation. Drawn under Zeiss 3 mm. 
apochromatic oil-immersion (1°40) with compensating ocular 18.] 
Figs. 1—19.—Bacillus flexilis. 
Fig. 1.—Ordinary vegetative individual, showing finely-granular, somewhat 
alveolar protoplasm, ete., and in which the outer layer is carefully focused. 
Fie. 2.—An individual in which the spiral filament is very clearly seen. 
Fig. 3.—Motile organism in which two fully-formed spores are seen. 
Figs. 4—7, more enlarged drawings of one end, showing de- 
velopment of spore. 
Fic. 4.—Beginning of spore formation. 
Vic. 5.—Later stage. 
Fie. 6.—Still later, formation of spore membrane. 
Fie. 7.—Still later, fully formed spore. 
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