202 BACTERIOLOGY. 



are not totally recovered as the food is increased. With 

 the guinea-pigs there is likewise at first a loss, but after 

 a short time the weight remains tolerably constant, and 

 is not as conspicuously affected by the increase in food 

 as one might expect. From the recorded temperatures 

 one sees the peculiar fluctuations mentioned. To just 

 what they are due it is impossible to say. It is mani- 

 fest that the normal temperature of these animals, if we 

 can speak of a normal temperature for animals present- 

 ing such fluctuations, is about a degree or more, Centi- 

 grade, higher than that of human beings. The animals 

 from which these charts were made were not inoculated, 

 nor were they subjected to any operative procedures 

 whatever, the only deviations from normal conditions 

 being the variations in the daily amount of food given. 

 In certain instances, however, there will be noticed a 

 constant tendency to diminution in weight, notwith- 

 standing the daily fluctuations, and after a time a con- 

 dition of extreme emaciation may be reached, the animal 

 often being reduced to from 50 to 60 per cent, of its 

 original weight. In other cases, after inoculations to 

 which the animal is not susceptible, rabbits in particular, 

 if properly fed, will frequently gain steadily in weight. 

 The condition of progressive emaciation just mentioned 

 is conspicuously seen after intra-venous inoculation of 

 rabbits with cultures of the bacillus typhi abdominalis and 

 of the bacterium coli commune referred to in the chapter 

 on the latter organism, and if looked for will doubtless 

 be seen to follow inoculation with other organisms 

 capable of producing chronic forms of infection, but 

 which are frequently considered non-pathogenic because 

 of their inability to induce acute conditions. Not infre- 

 quently in chronic infections there may be hardly any 



