SEDGWICK AND ^YINSLOW. — BACILLUS OF TYniOlD Fl.VER. 4,^0 
teuipcrature, itself inociilatea from one grown at Sif/ C. In the laier %vork the cul- 
tures were all kept at the room temperature. 
When experiments made on the culture obtained in November, lS98,gavc rcanlta 
somewhat different from those given hy the culture used in February, it wn=! decided 
that still a third culture from a different source must be compared with the first (wo. 
The results showed that the descendants of these different stocks exhiltitcd sli^dit 
though constant and persistent differences in their reaction to cold. Wc have called 
the cultures derived from these original sources "Races," for physiological rarof* 
they apparently must be considered. 
The first culture used, Race A, was obtained from the Boston City Hospital as n 
forty-hour-old blood-serum culture on February 23, 1898. Unfortunately, the history 
and tests applied to this culture in the Hospital were not recorded, beyond fhe fart 
had been isolated from an autopsy abo 
previously, bj 
differential method 
Race B was obtained by the kindness of Dr. M. W. Richardson of the Mn?^?achu- 
setts General Hospital in the middle of November, 1898, with the following history. 
It had been isolated from the spinal canal, in a case of typhoid meningitis. It gave 
typical reactions in media as follow^s : bouillon, very motile; litmus nu'lk. no conguliim, 
slight acid pi 
gar, no gas; peptone solution, no indol ; g 
stab, typical growth, no liquefaction ; arsenic bouillon (Thoinot), no growth ; Capaldi- 
Proskauer sol. No. 1, no growth ; potato, no visible growth ; tube medium of His, 
clouding without gas production; typhoid serum, perfect reaction. 
Race C was obtained, January 14, 1899, by the courtesy of Dr. Pratt of the Boston 
City Hospital. It had been isolated, December 30, from the peritoneal cavity in a 
case of peritonitis following typhoid fever. It gave typical growth.s on the ordinary 
media, gelatine, bouillon, and glycerin-agar ; it was motile in the hnnging drop; it 
gave no indol and no gas in glucose solution; it was decolorized by the Gram method 
and reacted to typhoid serum. 
Race D was isolated in the laboratory of the City Hospital, March 26, 1899, 
fr 
It was identified by the same tests used for Race C 
Results Obtained. 
The percentage reductions recorded in the subjoined tables (pp. 492-498), sum 
niarized in final form, are as follows: 
