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THE ACTINOMYCETES, Vol. II 



(h) dark brown (umbrinus) (c) chestnut 

 brown (badius), (d) reddish-brown (fuscus), 

 (e) yellow-rusty -brown (ferrugineus) , (f) 

 greenish-brown (hepaticus), (g) cinnamon- 

 brown (cinnamomeus) ; also beige, tan, and 

 ocher. 



9. Gray: (a) greenish-gray (griseus), (b) 

 ash-gray (cinercus), (c) white-gray (incanus), 



(d) brownish-gray (fumigatus), (e) reddish- 

 gray (murinus), (f) bluish-gray (plumbeus). 



10. Black: (a) gray-black (niger), (b) 

 coal black (ater), (c) brownish-pitch-black 

 (piceus), (d) greenish-jet-black (coracinus), 



(e) blue-black (atramentarius) . 



Appendix II 



Certain Important Media for the Study 

 of Actinomycetes 



Krainsky (1914) and Waksman and Curtis 

 (1916) were the first to report on the sig- 

 nificance of simple synthetic media in the 

 study of the morphological and cultural 

 properties of actinomycetes. Conn (1021) 

 made a careful comparison of the growth of 

 7.") cultures of actinomycetes on a large 

 tiumber of media. He came to the conclu- 

 sion that "extreme variation in chromo- 

 genesis is possible with some of the cultures 

 studied, according to the composition of 

 i he medium, and some cultures even vary 

 greatly when studied at different times on 

 the same medium. The appearance of one 

 of these organisms on any medium should 

 not be described until it has been cultivated 

 on several lots of this medium at different 

 times. No culture, moreover, can be con- 

 sidered nonchromogenic until it has been 

 studied on a great variety of different pro- 

 tein-free media." 



The following have been selected as rep- 

 resenting the more important media recom- 

 mended for the study of actinomycetes. All 

 constituents are reported in grams per liter. 

 /. Sucrose nitrate agar: 



Sucrose 30.0 gm 



NaN0 3 2.0 gm 



K 2 HP0 4 i.Ogm 



MgS0 4 -7H 2 0.5 gm 



KC1 0.5 gm 



FeS0 4 0.01 gm 



Agar 15.0 gm 



Distilled water 1000.0 ml 



pH 7.0 to 7.:; 

 This medium is frequently also known as 

 "Czapek's agar," or as "Czapek's solution 

 agar." Glycerol or glucose may besubstituted 

 for sucrose, giving glycerol-, or glucose-ni- 

 trate agar. Ammonium chloride may be sub- 

 stituted tor NaN0 3 , giving sucrose-ammo- 

 nium agar. 

 2. Glucose-asparaginc agar: 



Glucose 10.0 gm 



Asparagine 0.5 gm 



K 2 HP0 4 0.5 gm 



Agar 15.0 gm 



Distilled water 1000.0 ml 



pH 6.8 

 Meat extract (2.0 gm) may be added to this 

 medium. Tap water may be used. 

 ■ !. Glycerol-asparagine agar: 



Glycerol 10.0 gm 



Asparagine 1.0 gm 



KoHPO, 1.0 gm 



Agar 20.0 gm 



Tap water 1000.0 ml 



Adjust to pll 7.0 with NaOH. 



4. Glycerol-asparaginate agar I: 



Glycerol 35 . gm 



Ammonium lactate (5.5 gm 



Sodium asparaginate 3.5 gm 



K2HPO4 2.5 gm 



NaCl 5.0 gm 



CaCl 2 0.1 gm 



MgSO, 0.8 gm 



Agar 20.0 gm 



Distilled water 1000.0 nil 



This medium is often spoken of as Ushin- 

 sky's, especially when used as a solution, 

 without agar. 



5. Glycerol-asparaginate agar II: 



( rlycerol 10.0 gm 



Sodium asparaginate 1.0 gm 



