i So AIDS TO BACTERIOLOGY 



generally seen, though more (up to twenty) are often 

 found. The existence of a flagellum is uncertain. The 

 virus is destroyed by exposure to X rays or to a tempera- 

 ture of 48 C. for half an hour. 



T. 'pallidum is now accepted as the cause of syphilis. 

 It is found in the primary sore and neighbouring lymphatic 

 glands, in the papular and roseolar eruptions and condylo- 

 mata of the secondary lesions. It is also found but with 

 some difficulty and only in small numbers in gummatous 

 lesions. Considerable numbers of T. pallidum are found 

 in the liver, lungs, pancreas, spleen, thymus, and adrenals 

 of syphilitic foetuses. Noguchi demonstrated the presence 

 of this organism in the brains of patients dying of general 

 paralysis; Stoddart holds the view that the treponeme of 

 general paralysis is not absolutely identical with that of 

 syphilis. Moss has suggested that there is a special general - 

 paratysis-producing variety of the syphilitic organism. 



McDonagh thinks the protozoon enters the body while 

 in the spore phase, and that T. fallidum probably re- 

 presents the end phase of the life cycle and is a male. 

 McDonagh says that where extracellular development 

 (only described in chancres and condylomata) occurs, 

 the immature treponeme that is first formed resembles 

 the refringens type. 



T. pallidum can be cultivated by Noguchi's method; 

 material for inoculation is obtained not from human 

 lesions, but from the artificially infected testicular tissue 

 of the rabbit. This is introduced into serum water 

 to which a piece of sterile rabbit tissue (preferably kidney 

 or testicle) has been added. The surface of the medium 

 is covered with a layer of sterile paraffin. Once primary 

 culture has been effected strict anaerobiosis is not essential ; 

 and the organism can in subcultures be transferred to 

 solid media such as ascitic fluid agar. 



The treponemes can be separated from the bacteria 

 that usually contaminate the primary culture by letting 

 them grow through filters which retard the passage of 

 other organisms, or by growth in stab cultures where 

 the treponemes grow away from the line of puncture 

 into the surrounding medium while other bacteria fail 

 to do so. 



In ulcerating syphilitic lesions Spirochaeta refringens 

 sometimes accompanies T. pallidum. McDonagh (Lancet, 



