CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



411 



(4) Cool rapidly the receptacle, now 

 containing the cleaned filtered agar. 



(5) Remove the agar when set. 



(6) Mince finely by passing the agar 

 thru a mincing machine furnished 

 with a disc having small holes. 



(7) Spread the vermicular threads ob- 

 tained in shallow layers on trays. 



(8) Desiccate in a drying oven at 

 moderate temperature. 



(9) Reduce the desiccated material to 

 powder. 



(10) Preserve in the dry state. 



(11) Use for the preparation of media in 

 a strength of one per cent. 



Reference: Harvey (1921-22 p. 66, 67). 



SUBGROUP II-B 



Agar Media with All Other Constit- 

 uents Inorganic 



Basal or complete media containing agar; 

 all other constituents inorganic. 



Key to the Sections of Subgroup II B 



Ai. Nitrogen present as free or elementary 

 nitrogen.... Section 1 (Med. 1402-1410) 



A2. Nitrogen supplied as ammonium salts 

 Section 2 (Med. 1411-1424) 



A3. Nitrogen supplied as nitrites or ni- 

 trates Section 3 (Med. 1425-1430) 



SUBGROUP II-B. SECTION 1 



Basal or complete media containing agar 

 with inorganic salts. Nitrogen present as 

 free or atmospheric nitrogen only. 

 Ai. Containing salts of monovalent cations 

 only. 



Davis' Sodium Chloride Agar 1402 



Beijerinck's Thiosulphate Agar 1403 



As. Containing salts of monovalent and 



other cations. 

 Bi. Calcium salts added. 



Gordon's Basal Salt Agar 1404 



Carrel and Burrows' Locke's Solu- 

 tion Agar 1405 



Omeliansky's Basal Carbonate Agar. 1406 



Ashby's Salt Agar (Murray) 1407 



Winogradski's Salt Agar (Murray) . . 1408 

 B2. Calcium salts not added. 



Liot's Basal Salt Agar 1409 



Dox's Salt Agar (Tanner) 1410 



1402. Davis' Sodium Chloride Agar 



Constituents; 



1. Water 1000.0 cc. 



2. Agar 15.0 g. 



3. NaCl 5.0 g. 



Preparation: (1) Dissolve 2 and 3 in 1. 



(Pure or impure sugars may be added.) 



Sterilization: Not specified. 



Use: To produce chlamydospores by Sporo- 

 thrix schenckii. Smith and Smillie used 

 a similar medium to obtain coccidia 

 spores from sparrow feces. Teague and 

 Deibert studied the constituents neces- 

 sary for the growth of Unna-Ducrey's 

 bacillus and reported no growth on the 

 medium used. 



Variants: Smith and Smillie, and Teague 

 and Deibert dissolved 2.0% agar in a 

 0.5% aqueous NaCl solution. 



References: Davis (1914 p. 485), Smith and 

 Smillie (1917 p. 415), Teague and Deibert 

 (1922 p. 70). 



1403. Beijerinck's Thiosulphate Agar 

 Constituents : 



1. Water 1000.0 cc. 



2. NaoSaOs, 5H2O 5.0 g. 



3. K2HPO4 0.1 g. 



4. NaHC03 0-2 g. 



5. Agar 20.0 g. 



Preparation: (1) Dissolve 2, 3, 4 and 5 in 1. 

 Sterilization: Not specified. 



Use: Isolation of Thiobacillus denitrificans 



and T. thioparus. 

 Reference: Beijerinck (1903-04 p. 599). 



1404. Gordon's Basal Salt Agar 

 Constituents: 



1. Distilled water 1000.0 cc. 



2. K2HPO4 (0.1%) 1.0 g. 



3. MgS04 (0.2%) 2.0 g. 



4. CaCl. (0.01%) 0.1 g. 



5. NaCl (0.5%) 5.0 g. 



6. Agar (3.0%) 30.0 g. 



Preparation : 



(1) Dissolve 2, 3, 4, 5 and 3.0% of a 

 thoroughly washed and then dried 

 agar in 1. 



(2) Dissolve one of the added nutrients 

 in (1). 



Sterilization: Not specified in the abstract. 



Use: To determine nitrogen requirement of 

 some of the commoner pathogenic bac- 

 teria. 



