226 IMPORTANT VARIETIES OF FISSION-FUNGI. 



even in the cold, but not by Gram's method. The cap- 

 sules, which are colorless after the usual stain, may, how- 

 ever, be stained. (See Technical Appendix. ) 



Requirements as Regards Nutrient Media and 

 Oxygen. Grows luxuriantly upon all the nutrient media 

 employed, both with and without oxygen. 



Gelatin Plate. (a) Natural size. Superficial: Round 

 or roundish, moist, white colonies, with even border, 

 usually much elevated, rarely flat, with a slimy-fatty luster. 

 Deep : Roundish to whetstone-shaped, yellowish-white (15, 

 v). 



(6) Magnified fifty times. Superficial: Round colonies 

 with smooth border, reddish to yellowish-brown, trans- 

 parent only at the periphery. Sometimes there extend 

 outward from the center rays which appear as dark brown 

 thorns and points upon the lighter underlying part (15, 

 vn). Usually a structure can scarcely be distinguished. 

 Deep: Roundish to Avhetstone-shaped, smooth border, 

 brown, opaque (15, vi). 



Gelatin Stab. Stab : Well developed, yellowish-white, 

 like a string of pearls. Surface growth : Elevated, like the 

 head of a nail. The gelatin is sometimes a little brownish 

 about the puncture, but never liquefied (15, n). 



Agar Plate and Stab. Similar to the growth in gela- 

 tin, only the colonies are perhaps still more luxuriant and 

 moister. 



'Sometimes we observed in plates, instead of the roundish deep col- 

 onies, single deep veil-like spreading colonies, some of which are 

 reproduced in Plate 15, vin. 



Agar Streak. Growth spreading moderately, whitish- 

 yellow to gray, with a moist luster, much elevated, espe- 

 cially in the middle. The border is smooth, wavy, and 

 the periphery transparent. Water of condensation is 

 cloudy, with a slimy deposit (15, i). 



Bouillon Culture. Very cloudy, with a slimy deposit 

 at the bottom, which upon shaking becomes homogeneous. 

 Bouillon becomes somewhat thickened. 



Milk Culture. Not coagulated after twenty days. Abel 

 never found milk coagulated by true Bact. pneumonias, 

 but the opposite was observed by others ; for example, 



