322 IMPORTANT VARIETIES OF FISSION-FUNGI. 



usually provided with winding, anastomosing lines. The 

 deep colonies later appear irregular in form, with smooth 

 edges, opaque, usually with outgrowths at the periphery 

 (41, vm). 



Agar stab and streak like those of the Bac. suhtilis 

 (41, ii). 



Bouillon. — Moderately cloudy, often with pellicle 

 formation. 



Potato Culture. — Very similar to that of the Bac. 

 subtilis. The color is usually somewhat more yellow; the 

 mealy appearance also occurs (41, ix). 



Chemical Activities. — See remarks on page 307; no 

 indol, much H 2 S. 



Distribution. — Found by De Bary upon decomposing 

 cabbage leaves. The Bac. quercifolius Lehm. and 

 Detjen, from sausage, described from this institute by 

 Detjen (dissertation) in 1890, appears to be identical. 



Remarks. — The separation of this variety from the 

 subtilis is rather difficult ; it lacks the marked pellicle 

 formation upon the gelatin culture and the pronounced 

 formation of curls upon the gelatin plate. 



The following, described by Hiippe, is very closely re- 

 lated : 



Bacillus butyricus. Hiippe. (Mit. G. A. ii.) 

 (Plate 38, v-vn a.) 



Judging from our studies of a culture which we have cultivated for 

 six years, it seems to stand midway between the Bac. megatherium 

 and mesentericus. The thinness of the rods appears to be a result of 

 prolonged cultivation. Slender rods, 1.2-4 // long, only 0.3-0.5 // thick 

 (!), with ends moderately rounded. They are motile, because of 

 numerous peritrichous flagella, and stain by Gram's method. Upon 

 the gelatin plates there occur, as in the case of Bac. vulgatus, typhoid 

 forms ; still, they are usually much scalloped, and often have a crater- 

 shaped depression at the center (38, vi). Later the crummy center 

 enlarges at the expense of the outer transparent zone (38, vn) until 

 finally the whole colony breaks up. 



Upon the gelatin stab culture a pellicle is likewise to be found, only 

 the Bac. butyr. liquefies a little more slowly. The agar plate culture 

 is exactly like that of the Bac. mesentericus, perhaps a little more 

 delicate ; also the agar streak and stab, except that the brown color is 

 absent. The potato culture, on the contrary, presents no mesh work, 

 and is not distinguishable from the megatherium (38, v). Bouillon 



