328 IMPORTANT VARIETIES OF FISSION-FUNGI. 



same, others form thick, moist, white growths, still others liquefy and 

 form pellicles, and yet others resemble subtilis colonies. Upon the 

 gelatin stab is formed a growth like typhoid, which still, after a 

 longer time, slowly sinks in, with the form of a funnel. Potato cul- 

 tures at first are like Bact. coli ; later the cultures acquire a rose-color, 

 which finally is transformed into reddish-brown. Agar stab culture 

 is delicate, whitish-gray, transparent, moistly shining; later a netted 

 film forms upon the surface. Bouillon becomes faintly cloudy, with 

 a thin pellicle upon the surface. Milk is not coagulated, reaction 

 feebly alkaline. H 2 S and gas are not produced. 



Bacillus aterrimus. (Biel.) Lehm. and Neum. 



A very striking, aerobic, motile, sporulating bacillus, possessing 

 all the peculiarities given on page 306, and producing black pig- 

 ment. The gelatin plate cultures appear to resemble Bac. subtilis and 

 vulgatus. Gelatin stab cultures present funnel-shaped liquefaction 

 without coloration. Upon potatoes at first grayish-blue, then brown- 

 ish-black, wrinkled, moist pellicles are formed, the potato being black 

 throughout. Agar cultures become brown with yellowish-brown films. 

 The organism is not pathogenic. Compare Biel (C. B. L. n, 137) and 

 Lunt (I, c, 572) regarding B. mesentericus niger. Gorini's closely 

 related Bac. lactis niger (C. B. xx, 94) we obtained from Krai 

 in 1895 and studied. It no more showed any chromogenesis, and 

 grew as a flat deposit upon potato, resembling the Bact. coli. Spon- 

 taneous motion could not be seen. It is questionable whether the 

 insufficiently described Bac. melanosporus Eidam of Schroter belongs 

 here. 



Bacillus liodermos. (Fltigge.) Lehm. and Neum. 



Bacillus mesentericus liodermos Fltigge. 



This bacillus, described by Fltigge as short and very actively motile, 

 we have not certainly encountered during recent years. The gelatin 

 growths in plates and in the stab are like Bac. vulgatus. The potato 

 culture forms a smooth, shining, yellowish-white, syrupy growth, 

 which only after several days becomes a little wrinkled and cloudy. 

 The Bacillus mucosus Zimmermann (n, p. 8), from slimy water, ap- 

 pears to have some relationship. 



Bacillus gangraenae pulps. Arkovy. 



Synonyms. — Bacillus fuscans Miller? Caries fungus of 

 Galippe and Vignal, Caries fungus of Jung. 



Literature.— Arkovy (C. B. xxiii, 917). 



According to the investigations of Dr. Zierler, made in 

 the Wiirzburg hygienic institute, which deviate somewhat 



