268 F. JEFFREY BELL. 



red colour, which was due to its neutral or alkaline re- 

 action. They appear to propagate by fission. 



Cohn now describes two new species, the leading charac- 

 ters of which must be rapidly enumerated : 



9. Rhabdomonas rosea, n. sp. This form, which also 

 came from Kahla, had a spindle-shaped appearance, with pale 

 rosy-red corpuscles within, of '0038 — '005 mm, and a length 

 •02 — '08 mm. ; the cells were single and the corpuscles were 

 dark, and highly refractive, in addition to which vacuoles 

 were observed at the middle and ends ; their movement was 

 a trembling backwards and forwards, with a continual turn- 

 ing around their long axis ; he has no doubt of the existence 

 of a flagellum, though he only once saw it with distinct- 

 ness. 



10. Monas Warmingii, n. sp., was obtained from Dr. 

 Warming, of Copenhagen, who found it in pools of brackish 

 water, where marine plants were decaying, in the company 

 of nearly all the forms — except Ascococcus — which have been 

 described above ; it resembled, save that it was broader, 

 Monas Okenii; the body was clear, and the contained 

 protoplasm firm and of a pale red, filled with dark red gra- 

 nules, only at the rounded extremities ; length '015 — '02 mm., 

 breadth "008 ram. ; their movement was irregular (taumelnd), 

 but much more active than that of M. Okenii ; posteriorly, 

 there projected a flagellum; when division of the cells is 

 about to occur, the middle, Avhich was before devoid of 

 granules, becomes filled with them, so that when division is 

 accomplished the two new cells have the characteristic ter- 

 minal groups of granules, at once ; this form also differs from 

 M. vinosa of Ehrenberg in its larger size. 



11. Ophidomonas sanguinea, Ehr., a form of varying size 

 and breadth, which Cohn found in Dr. Warming's water, is 

 thought by him, after along consideration, to be the same as that 

 discovered by Ehrenberg in 1836. Although, indeed, since 

 Cohn has himself shown, that Spirillum volutans has a fine 

 flagellum at each end,^ there is no difference between Spi- 

 rillum and Ophidomonas ; unless the smaller species (*S^. termo, 

 S. undula) be shown not to possess flagella, when the generic 

 term Spirillum would be justly theirs. 



12. But a more important question is the relation of the 

 Bacteria to the Monads ; on the one hand, it may be said 

 that the Monads are Bacteria. The Monad form here called 

 Clathrocystis roseo-persicina was considered by Prof. Ray 

 Lankester as a " peach-coloured Bacterium ;" and Ehrenberg 

 supposes that all the Bacteria possess cilia, (Frau Liiders, as 



' ♦ Quart. Journ. Mic. Sci.,' April, 1873. 



