BACTERIOLOGY OF THE SALIVA OF HELODERMA 



SUSPECTUM. 



By D. Rivas. 



In the course of investigations into the toxic action of the poison of Helo- 

 derma suspectum, it was necessary to compare the effect of fresh and heated 

 saliva of these reptiles. It had been found* that if tested on guinea-pigs the 

 fresh venom caused, besides the typical symptoms common to both the heated 

 and fresh venom, certain inflammatory reactions which were absent in those 

 guinea-pigs which had been injected with heated venom. It was of interest, 

 therefore, to determine which organism might be responsible for the inflam- 

 matory lesions found in guinea-pigs after injection of fresh venom, and with 

 this point in view experiments were carried out to isolate the organism respon- 

 sible and to determine whether the organism was present frequently in the 

 saliva of these reptiles. 



A guinea-pig which had received an intraperitoneal injection of fresh 

 venom and had been dead for about 3 hours was brought to me for bacterio- 

 logical examination. 



Autopsy. Point of inoculation slightly swollen and edematous; slight peritoneal exudate, 

 but no congestion. Spleen enlarged; other organs normal. 



Microscopical examination. Smears made from point of inoculation, peritoneal exudate, 

 blood, and organs showed, among other bacteria, a thin Gram negative bacillus which in 

 pure cultures corresponded to the morphological and biological features of Bacillus coli com- 

 munis; it fermented dextrose, produced indol, coagulated milk, did not liquefy gelatine, was 

 negative to test No. 1 and test No 3, and positive to test No. 2 (D. Rivas, Journal of Infec- 

 tious Diseases, vol. 4, November 1907, p. 641, and Journal of Medical Research, March 1908.) 



After obtaining similar results with a number of other guinea-pigs which 

 directly after death presented the same post-mortem appearance as the first 

 animal, experiments were made to determine the virulence of the cultures iso- 

 lated. A number of guinea-pigs were used for the experiment; some were 

 injected subcutaneously and others intraperitoneally with a small amount of 

 the scraping of a 24-hour agar culture dissolved in sterile salt solution. All 

 injected guinea-pigs died, some a few days after the inoculation and others 

 on the day of the injection, and in one instance the culture was found to be 

 so virulent that the guinea-pig died 3 hours after the intraperitoneal injection. 

 Bacteriological examination of the point of inoculation, blood, and organs of 

 the dead guinea-pigs revealed in each case the presence of the bacillus used 

 for injection. 



*Cf. the communication by E. Cooke and Leo Loeb. 



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