GROUP II. LIQUEFIABLE AGAR MEDIA 



SUBGROUPS OF LIQUEFIABLE AGAR under one atmosphere pressure for 



MEDIA 15 minutes. 

 Ai. Water and agar only. ^^^- Cultivation of amoebae, algae, para- 

 Subgroup II A. (Med. 1395-1401) ^^*^^ fiagellata and ciliata. Frost used a 

 Aj. Water and agar with other constituents. similar medium to study the antagonistic 

 Bi. All other constituents inorganic. ^^^'°^ °^ bacteria. 



Subgroup II B. (Med. 1402-1430) Variants: 



B2. Containing one or more organic con- ^^^ ^^°^* studied the antagonistic action 



stituent (other than agar). between saprophytic organisms and 



Subgroup II C. (Med. 1431-2198) ^- ^yP^osus in medium prepared by 



the following method: 



SUBGROUP II-A (1) Dissolve 2.0% agar in water. 



(2) Sterilize. 



Media Consisting of Water and Agar (3) Pour in deep Petri dish to cool. 



Only (^) When solid, cut in little squares 



with sterile knife. 



Basal or complete media containing agar (5) gtab with needle seeded with organ- 



and water only. Here may be included jsm to be studied. 



methods used for purifying agar for use in (g) Seal top of block with red hot nail 



media. It is rarely used without the addi- head 



tion of other constituents. (7) pi^ce by means of sterile forceps 



Ai. Agar and water only. (Agar not into broth culture of other 



P""fied.) organism. 



Tischutkin's Agar Solution 1395 Frost reported that if there was antag- 



Pringsheim's Basal Agar 1396 onistic action, no growth occurred in 



A2. Agar purified by washing with water. the block. 



Beijerinck's Basal Agar Solution (b) Walker cultivated parasitic fiagellata 



(S™i*h) 1397 and ciliata in a 2.0% agar solution 



Ayers, Mudge and Rupp's Washed adjusted to an alkalinity of 1.0% to 



^g^^ 1398 phenolphthalein. 



As. Agar purified by washing with alco- References: Tischutkin (1897 p. 185), Frost 



hoi, acids, etc. (19Q4 p go4). Walker (1908 p. 490). 



Dominikiewicz's Purified Agar 1399 



Cunningham's Purified Agar 1400 ^■,r^< r, , u , , -c 1 a 



TT 7 T. -c J A , .^, 1^96. Pringsheim's Basal Agar 



Harvey's Purified Agar 1401 



1395. Tischutkin's Agar Solution ^TwZT. '. 1000.0 cc. 



Constituents: 2. Agar 2.5 g. 



1. Water 1000.0 cc. Preparation: (1) Dissolve 2 and one of the 



2. Agar (1.0%) 10.0 g. added nutrients in 1. 



Preparation: Sterilization: Not specified. 



(1) Dissolve 1.0% agar (best quality) in Use: To study nitrogen assimilation by 

 water by steaming in the autoclave Clostridium americanum and Azotobac- 

 under 2 atmospheres pressure for ter chroococcum with Bacillus gelaticus. 

 10 minutes. Author reported that Bacillus gelaticus 



(2) Filter thru paper. with Clostridium americanum assimilated 



(3) Tube. more nitrogen than did Bacillus gelaticus 

 Sterilization: Sterilize in the autoclave with Azotobacter chroococcum. 



408 



