1138 



MANUAL OF DETERMINATIVE BACTERIOLOGY 



26. Phagus testabilisH. {loc.cit., 155). 

 From Latin testabilis, able to bear wit- 

 ness, in reference to evidence that this 

 bacteriophage has given, by virtue of its 

 easy destruction when heated in spores, 

 against the hypothesis of frequent spon- 

 taneous origin of bacteriophage from the 

 bacterial host. 



Common name : Bacillus megaihcrivm 

 bacteriophage. 



Host : Bacillus megatherium De Bary. 



Geographical distribution : United 

 States. 



Induced disease : Plaques 0.5 mm or less 

 in diameter, with surrounding translu- 

 cent zone. 



Thermal inactivation : In vitro, at 75° 

 C in 10 minutes. Spores from infected 

 cultures, after being heated for 10 min- 

 utes at 80° C, regularly give rise to sub- 

 cultures that do not show the presence of 

 this bacteriophage spontaneously during 

 subsequent growth but that are sus- 

 ceptible to lysis if the bacteriophage is 

 again introduced. 



Literature: Adant, Compt. rend. Soc. 

 Biol., Paris, 99, 1928, 1246; Cowles, Jour. 

 Bact., £0, 1930, 15-23. 



26. Phagus indomitus H. {loc. cit., 

 156). From Latin indomitus, unre- 

 strained, in reference to the ability of this 

 bacteriophage to increase after heat treat- 

 ment of infected spores. 



Common name : Bacillus mycoides bac- 

 teriophage. 



Host : Bacillus mycoides Fliigge, some 

 strains. 



Insusceptible species : Bacillus cereus 

 Frankland and Frankland, B. stibiilis 

 Cohn emend. Prazmowski, B. mega- 

 therium De Bary, B. anthracis Cohn 

 emend. Koch. Some strains of B. my- 

 coides. 



Geographical distribution. United 

 States. 



Induced disease: Large plaques, with 

 some secondary growth of host organism. 



Thermal inactivation : In vitro, at 75° C 

 in 10 minutes. Spores from infected cul- 

 tures, heated at 90° C for 10 minutes give 



no bacteriophage on grinding, but lytic 

 cultures when grown. 



liiterature : Lewis and Worley, Jour. 

 Bact., 32, 1936, 195-198. 



27. Phagus subvertens H. {loc. cit., 

 156). From Latin subvertere, to subvert, 

 in reference to suspected action of this 

 bacteriophage in causing running-out of 

 alfalfa fields through destruction of 

 nodule organisms. 



Common name : Rhizobium legumino- 

 sarum bacteriophage. 



Host : Rhizobium leguminosariim 

 Frank. It has been shown that this 

 bacteriophage is unable to increase in 

 clover roots without the nodule-forming 

 organism, R. Icguminosarum, and that 

 the bacteriophage plays no obviously 

 essential role in nodule formation. 



Induced disease : Very small plaques, 

 with edges not sharply defined. 



Thermal inactivation: At 60° C in 30 

 minutes. 



Other properties: Not inactivated by 

 drying for 2 months. 



Literature: Gerretsen et al.. Cent. f. 

 Bakt., II Abt., 60, 1923, 311-316; Grijns, 

 ibid., 71, 1927, 248-251; Hitchner, Jour. 

 Bact., 19, 1930, 191-201; Vandecaveye 

 and Katznelson, Jour. Bact., 31, 1936, 

 465-477. 



28. Phagus ineptus H. (loc. cit., 157). 

 From Latin ineptus, unsuitable, in refer- 

 ence to inability of this bacteriophage to 

 adapt itself to lysis of strain RW of its 

 host. 



Common name : Streptococcus bacterio- 

 phage R. 



Host : Streptococcus cremoris Orla-Jen- 

 sen, strain R. 



Insusceptible species : Streptococcus 

 cremoris, strain RW. 



Geographical distribution : New Zea- 

 land. 



Induced disease : Plaques 0.25 to 0.6 

 mm in diameter. 



Serological relationships : Antisera spe- 

 cific for streptococcus bacteriophage RW 



