BACTERIUM VIOLAOEUM. 277 



brick-red or orange-red color. This, however, according to our more 

 recent observations, is not constant; prodigiosum may grow with 

 orange, and liiliense with bluish-red color. The formation of alkali 

 is most important as to the color: with abundant production of alkali 

 it is yellowish-red; in other cases, bluish-red. We also found to be 

 absolutely identical Bacterium miniaceum ' (Zimmermann, L. and 

 N.) and the Bacterium indicum (Koch, L. and N.), isolated by Koch 

 from an Indian monkey, of which we obtained beautiful red cultures 

 from Krai and carefully studied them. 



It is very probable that these are also identical : 



Bacterium of red pus Ferchmin (C. B. xili, 103), which differs in 

 being non-motile and staining by Gram's method. 



Red water-bacillus Lustig (C. B. viil, 33). 



Bacterium plymuthicum Fischer. (L. and N.) Compare Voges 

 (C. B. XIV, 301). 



Bacillus fuchsinus Boekbout and Otto de Vries (C. B. L. IV, 

 497). 



The following is, at any rate, closely related. 



Bacterium piscatorum. Lehm. and Neum. 



Microbe rouge de la sardine of the French. Causes, in combination 

 with an anaerobic bacillus, panaritium in fishermen, apparently 

 originating in spoiled bait. In boxes of sardines it causes a red color 

 (DuBois Saint Severin, A. P., 1894, 152). The pigment is soluble in 

 water (?), usually poorly developed upon agar, and is produced at 37°- 

 39° More extensive studies are required to establish the constancy of 

 these characteristics. 



Bacterium violaceum. (J. Schroter.) L. and N.^ 



(Plate 23.) 



Synonym. — Compare page 279. Bact. janthinum Zopf. 

 Schroter' s name is older. 



Microscopic Appearance. — Thin rods, 1.6-5// long, 

 0.5-0.8 fj. thick, with rounded ends; the smallest are often 

 oval; sometimes threads form. In the interior unstained 

 areas sometimes remind one of chicken cholera. 



' What we obtained from Krdl as Bac. rosaceus metalloides 

 Dowdeswell is entirely different. We have called this Bact. rosaceum, 

 and found it to be a fine, small, motile rod, which something grows 

 like the Bact. coli on ordinary media, but with a brick-red color. 

 The pigment is not prodigiosin. Milk and bouillon present brick-red 

 pellicles. No gas is formed from grape-sugar. Milk is not coagulated. 

 Not stained by Gram's method. 



2 Twice in cultures, according to Migula's method, upon quince- 

 juice we have seen pictures which may have been spores. 



