228 APPLIED BACTERIOLOGY 



in the form of cocci arranged in chains or threads, which 

 freely interlace to form a network in the centre of the 

 colony. Bostrom has proved that these filaments are the 

 active portion, and could be cultivated on blood serum or 

 agar, while from the club-shaped portions he did not obtain 

 any growths. Crookshank has found that the organism is 

 more easily cultivated from man than from animals, and 

 that the most satisfactory medium is glycerine agar. After 

 repeated subculture the growths exhibit very peculiar forms, 

 a good collection of which is to be seen at King's College. 

 The pathogenicity of the organism has been shown experi- 

 mentally by injecting a pure culture into the peritoneum 

 of rabbits and into the subcutaneous tissues of calves, and 

 in each case a typical actinomycosis has resulted. Kan- 

 thaek is of the opinion that ' madura disease ' is produced 

 by the same or a similar organism. 



YELLOW FEVER. 



Specific organism at present unknown — Dr. Carmona's method of 

 securing immunity by the use of urine. 



This disease is endemic in the West Indies, Mexico and 

 the West African coast. Various organisms have been 

 described by different observers as the specific cause of this 

 disease, but up to the present it is uncertain which is the 

 specific organism. The method of conveyance of the disease 

 is also unknown. It was formerly regarded as akin to 

 malaria, but it has far more points of resemblance to cholera 

 in its etiology. In the year 1892 Sternberg suggested the 

 employment of the blood serum of convalescent patients as 

 a means of conferring immunity on persons about to proceed 

 to districts where the disease is prevalent. 



Some years previous to this, however. Dr. Manuel 

 Carmona Y Valle, of Mexico (Journal of American Public 



