MICROCOCCUS CORALLIOIDES. 175 



there is formation of acid, early there is marked stickiness (tenacity 1 ), 

 after a few days coagulation. Optimum 20. Growth occurs from 11 

 to 35. It is perhaps a streptococcus. 



Micrococcus acidi lactis (Kriiger) (C. B. vii, 425, 

 464, 493 ). 



Oval coccus, forming diplococci and tetrads, from 1.0 /* to 1.5 ft in 

 diameter. It is a facultative anaerobe. Eound, white colonies in 

 gelatin, with ragged border. Gelatin is liquefied. Gelatin stab. Stab: 

 Granular, white growth. Surface growth: White and later sinking 

 downward. From milk-sugar it forms lactic acid. Milk is coagulated 

 in five days at from 15 to 35, then the albuminous bodies are pep- 

 tonized with the production of a sticky character and a pasty odor. 



Micrococcus coronatus (Fliigge) (Ed. iii, p. i78). 



Round cocci, from 0.8 fj- to 1.6 //. Gelatin plate. Natural size: At 

 first small, white disks, which, when they are on the surface, have a 

 broad zone of liquefaction. At this stage, if magnified sixty times, 

 the colonies appear as gray, coarsely granular disks, with ragged bor- 

 ders, and later they break up into fragments and crumbs. The picture 

 of the natural-sized colonies later is quite changed; while a yellowish- 

 white, irregular clump lies at the bottom of the shallow funnel of 

 liquefaction, the clear funnel of liquid is surrounded by a zone of 

 sturdy, irregular points and outgrowths, which make the picture very 

 striking. The gelatin stab culture resembles that in the plate. 



Agar plate : Deep colonies, round, white, almost opaque. Superficial, 

 at first round, then ragged, tabulated, wavy, luxuriantly developed. 

 Agar streak: Grayish-white, broad, jagged, somewhat dry. Potato 

 culture : Similar. Bouillon : Slightly cloudy with sediment. No in- 

 dol, a trace of H 2 S is formed. Milk becomes gelatinous in ten days ; 

 after fourteen days it is coagulated with a minimal acid reaction. 



Found by Flligge many times in examinations of air, by us in ex- 

 amination of smegma. 



Micrococcus corallioides (Zimmermann) (ii, p. 72). 



According to Zimmermann's description it resembles the preceding, 

 yet is entirely different. Gelatin plate. Natural size : Colonies appear 

 as white, somewhat irregular masses, which after eighty hours form 

 outgrowths all around, so that finally they lie in the half liquefied 

 gelatin, with radiating, often branched, formations extending in all 

 directions. Magnified one hundred times the masses of bacteria appear 

 granular. Also the milk-white growth at the top of the gelatin stab 

 sends out indistinct outgrowths. Upon agar a broad, milk-white 

 growth, upon potato very little growth. Meat-infusion is uniformly 

 cloudy. Found by Zimmermann in w r ater. 



1 Weigmann's Micr. of tenacious milk does not liquefy gelatin. 



