CHAPTER XI 



ENDOMYCETALES— EREMASCACEAE IMPERFECTAE 



The species to be discussed may or may not belong in the Endomycetales, 

 since under certain environmental conditions the vegetative stages of many 

 groups may assume a yeastlike appearance. However, when suitable media are 

 employed, it is probable that ascospores will be formed in many species at pres- 

 ent considered as imperfect. Judging from previous cases, we may anticipate 

 that the ascosporic stage will place them definitely in the Eremascaceae. 



Since cultural studies seem essential in attempting to differentiate the 

 species of a group where the morphology seems variable, the following pro- 

 cedures, advocated by Redaelli and Ciferri (1929), by Talice (1930), and by 

 Langeron & Talice (1932), may be considered as standard until better are pro- 

 duced. They include most of the good features already advocated by Castel- 

 lani during the previous two decades. 



The fungus is easiest isolated on carrot agar,* or Sabouraud glucose 

 agar.f Spore formation is sought on Gorodkova agar. Cultures are incubated 

 at 20°, 30°, and 37° C. From information gained from these cultures optimum 

 temperature may be determined more accurately if desired. 



Comparative cultures may be made on the following media : Raulin, acid, 

 or neutral solution, decoctions of carrot or potato, t malt extract solution 

 (without hops), malt agar (2% agar), 2% glucose agar and corn meal agar 

 (recommended by Smith & Sano, 1933) ; malt gelatin, carrot gelatin; glucose 

 meat broth with 0.5% methylene blue, skimmed milk and peptone sugar broth 

 (formula of the Committee of the Society of American Bacteriologists). 



Descriptions of the colonies on the above-mentioned media should be 

 recorded after 1, 2, 4, 7, 10, and 30 days and even 60 and 90 days are often 

 useful. A microscopic examination should be made on the second, fourth, 

 tenth, thirtieth, sixtieth, and ninetieth days, on the latter days especial search 

 being made for signs of copulation, and ascospore formation. Material should 

 be examined from the bottom growth and pellicle in liquid media, and from 

 the center and edge of the colony on solid media. The material may be 

 mounted in glycerol, lactophenol, or Lugol's solution (water 11 c.c, potassium 

 iodide 2 gm., iodine crystals 1 gm.). They may be stained Avith ZiehFs carbol- 

 fuchsin, Loeffler's alkaline methylene blue, or Ehrlich's anilin methyl [gentian] 

 violet (methods of the Committee of the Soc. Am. Bact.). The cells should 



*One kilogram of carrots is washed, triturated, and boiled in 1 liter of water for 3 hours. 

 The solution is strained through cheesecloth, cooled. Altered through paper, made up to volume, 

 and 20 gm. agar are added. 



tAgar 18 gm.. White's [W^itte?] peptone 30 gm., and glucose 40 gm., water 1 liter. 



JTalice recommends the following: Reduce 20 gm. of potato to pulp, suspend in 1,000 c.c. 

 water, boil for 15 minutes, filter through cotton, replace water lost by evaporation, distribute 

 to tubes, and sterilize at 120° for 20 minutes. It should be noted that this solution is about 

 1/10 the concentration usually employed in Thaxter's potato agar. The more concentrated 

 solution is said not to give such good results. 



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