TREPONEMA PALLIDUM 2 19 



halteridium stage of trypanosome existence. They are to be found 

 in the juice obtained by splenic puncture. On the rare occasions 

 they have been met in the blood they were within a leucocyte. 

 The transmission is unknown. 



TREPONEMA PALLIDUM (Schaudinn). 



(Spirochaeta Pallida.) 



Treponema Pallidum. There has been some discussion as to 

 the proper classification but now this organism is usually placed 

 among the Flagellata, genus Treponema, as it does not possess an 

 undulating membrane, is flagellated, is of stiff and regular shape, 

 and multiplies by longitudinal division. 



Morphology and Stains. This organism is extremely delicate 

 in structure, from 4 to 14/1 in length and about .3/4 in width; has 

 from 3 to 12 turns or bends, and its ends are delicately pointed. 

 Its curves form a large arc of a small circle. The Sp. refringens 

 curves form a small arc, frequently irregular, of a larger circle. 

 It multiplies by both transverse and longitudinal division. As this 

 organism is stained with difficulty it requires a special one, that of 

 Giemsa yielding the best results. Aniline gentian violet, Romanow- 

 sky's, and Leishman's stains also color it. It may be stained in 

 tissues by silver and pyrogallic acid methods. 



Habitat. It has not been found in tissues of normal persons, or 

 those ill with carcinoma, tuberculosis, etc., but only in the tissues 

 of individuals suffering with syphilis. It is a strict parasite. 



Vitality. Nothing is known of its ability to withstand the action 

 of chemicals, light, heat, or other deleterious agencies. Glycerine 

 destroys its motility. 



The Treponema pallidum has now fulfilled the postulates of 

 Koch. It can be cultivated from human lesions (with some 

 difficulty to be sure), it can be implanted in animals (monkeys and 

 rabbits) and there reproduce syphilitic lesions; and it can be 

 recultivated from them. In these experimental diseases it retains 



