BACILLUS VULGATUS. 325 



Agar Streak. — Luxuriant growth, with a wavy scal- 

 loped border, grayish-white, with a fatty luster, especially 

 after a longer time becoming covered with numerous, 

 irregular, considerably elevated folds. Toward the edge 

 it is more transparent. The water of condensation is clear, 

 and upon the surface of the same a firm film is formed 

 (42, n). This description answers for the agar stab 

 (42, m). 



Bouillon. — A little cloudy, upon the surface a firm, 

 grayish-white film, which is not broken up by shaking. 



Milk Culture. — Slimy coagulum formed ; strong alka- 

 line reaction. Sometimes no coagulation occurs. 



Potato Culture. — Exceedingly variable. The typical 

 form at any rate presents abundant tortuous and confused 

 more or less padded elevations, rising and falling precipi- 

 tously, not unlike intestinal coils (42, x). The color is 

 partly whitish-gray, partly yellowish, yellow, or even rosy 

 brown. The coils may also be widely padded (38, ix) or 

 appear as thick, moistly glistening elevations (like Bact. 

 coli) (38, viii). 



Chemical Activities. — See remarks on page 306. No 

 indol is produced and little H 2 S. 



Distribution. — Common in soil, thus a frequent con- 

 tamination of our potato cultures (potato bacillus!). Also 

 found in the intestine and in sausage (Detjen, Serafini). 



Practical importance is slight. In incompletely unster- 

 ilized milk it, like the related varieties, occasionally 

 produces a gradual coagulation with strong alkaline 

 reaction, and later a solution of the coagulum with pro- 

 duction of bitter- tasting, injurious substances. 



The ability of the bacillus to sometimes produce abun- 

 dant quantities of a slimy carbohydrate, especially in feebly 

 acid bread, through swelling of its membrane, at times 

 becomes troublesome. J. Vogel (Z. H. xxvi, 398; there 

 also the literature), who has carried out in Hamburg a 

 special study upon the bacilli of viscid bread, found 

 especially two varieties of bacilli concerned with it: Bacil- 

 lus mesentericus panis viscosi II Vogel, which essen- 

 tially completely corresponds with the bacillus mesen- 

 tericus L. and N. (see below), and B. m. p. viscosi I, 

 which is distinguished by lack of motility, and by the 



