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, ii ). 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, vm). 



Chemical Activities. See remarks on page 306. No 

 indol is produced and little H.j3. 



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 



