MICROSPIRA COMMA. 467 



in very close relation to the material composing the 

 bodies of the bacteria themselves, and is probably an 

 integral constituent of them, for the vitality of the 

 cholera spirilla can be destroyed by means of chloro- 

 form of thymol, or by drying, without apparently any 

 alteration of this poisonous body. Absolute alcohol, 

 concentrated solutions of neutral salts, and a temper- 

 ature of 100 C., decompose this substance, leaving 

 intact secondary poisons which possess a similar physi- 

 ological activity, but only when given in from ten to 

 twenty times the dose necessary to produce the same 

 effects with the primary poison. 



EXPERIMENTS UPON ANIMALS. As a result of ex- 

 periments for the purpose of determining if the disease 

 can be produced in any of the lower animals it has been 

 found that white mice, monkeys, cats, dogs, poultry, and 

 many other animals are not susceptible to infection by the 

 methods usually employed in inoculation experiments. 

 When animals are fed on pure cultures of the comma 

 bacillus no effect is produced, and the organisms cannot 

 be obtained from the stomach or intestines. They are 

 destroyed in the stomach, and do not reach the intes- 

 tines ; they are not demonstrable in the faeces of these 

 animals. Intravascular injections of a pure culture 

 into rabbits are followed by an illness, from which 

 the animals usually recover in from two to three days ; 

 intraperitoneal injections into white mice are, as a rule, 

 followed by death in from twenty-four to forty-eight 

 hours, the conditions in both instances most probably 

 resulting from the toxic activities of the specific poisons 

 contained in the cultures used. 



None of the lower animals suffer spontaneously from 

 Asiatic cholera. 



