290 IMPORTANT VARIETIES OF FISSION-FUNGI. 



to whetstone-shaped and yellowish. Superficial (after 

 three days) : Irregularly jagged lobulation, with a moist 

 luster, a little elevated, sharply outlined from the surround- 

 ing medium, yellowish to grayish- white (28, vi). Later 

 they become grayish to brownish-lavender. The gelatin 

 is variously colored. (See also 28, vn. ) 



(6) Magnified fifty times. Deep : Round or roundish, 

 yellowish, delicately granular (28, vni i). Superficial: 

 In the youngest stages are not distinguishable from those 

 of Bact. typhi and coli. Also later they are still very 

 similar to them, only the colonies appear much more 

 delicately granular. Often the original colony appears at 

 the middle as a yellowish-brown nucleus. Every possible 

 variation of form, structure, and color is observed. The 

 color usually is yellowish and the form irregularly lobu- 

 lated (28, vm e). 



Gelatin Stab. — Stab: Not characteristic, thread-like. 

 Surface growth : From whitish and bluish-gray to greenish- 

 yellow, with a moist luster, slimy. The color of the gela- 

 tin varies exceedingly. A culture obtained from Berlin 

 in the summer of 1895 usually furnished light to dark 

 blue growths, while a culture of our own, which had been 

 cultivated in the institute for about six years, exhibited, 

 upon the same nutrient medium, brownish-green, dark 

 brown, and light yellowish-green growths with more or less 

 fluorescence. A Bact. syncyaneum cyaneofluorescens 

 Zangemeister (C. B. xviii, 321) behaved very similarly. 

 A year later also the Berlin culture produced no blue color 

 upon either acid or alkaline nutrient media, but only dirty 

 colors, from light or dark brown to light yellowish-green 

 and deep brownish-green (27, i, n, in). (Compare also 

 27, iv. ) A culture freshly isolated from milk in Wiirz- 

 burg gave beautiful blue pigment with little fluorescence. 



Agar Plate. — (a) Natural size: Like those on the gela- 

 tin plate. 



(6) Magnified fifty times. Deep : Roundish to whetstone- 

 shaped, yellow, gray, or brownish, with even border, 

 homogeneous, shaded. Superficial: Round to roundish, 

 smooth edge, light yellowish to grayish-brown, homogen- 

 eously shaded or finely granular. It is similar to the colony 

 of Bact. fluorescens (28, v). 



