394 Transactions of the Society. 



This inference was based upon morphological resemblance, as 

 indicated by Friedlander's description of his coccus, and upon the 

 fact that I had demonstrated the frequent, if not constant, presence 

 of my M. Pasteuri in the rusty sputa of patients with pneumonia. 

 I have since had an opportunity to study the characters of Fried- 

 lander's coccus in a culture obtained from Mr. Watson Cheyne, and 

 also in one presented to me by Dr. Frobenius during a recent visit 

 to BerUn, and I recognize essential differences in the mode of 

 growth of the two organisms, which make it apparent that they 

 are not identical, or, as I suggested, simply " pathogenic varieties 

 of the same species." 



Friedlander has shown that his coccus, or " bacterium," does 

 not kill rabbits, and it grows readily at comparatively low tem- 

 peratures, 20° to 25° C. On the other hand, M. Pasteuri is fatal to 

 rabbits and requires for its development a temperature not obtained 

 in temperate climates, except by the use of an incubating oven, 

 30° to 35° C. Moreover, the nail-shaped growth of the cultures 

 in gelatin, which Friedlander's coccus presents, is quite different 

 from the appearance presented by a culture of M. Pasteuri in 

 agar-agar. The fact that a temperature above the melting point 

 of gelatin is required for the development of the last-mentioned 

 organism makes it impossible to cultivate it in solid gelatin, but it 

 grows readily in an incubating oven in liquefied flesh-pepton- 

 gelatin, or in an infusion of the flesh of a chicken or rabbit which 

 has been rendered neutral or slightly alkaline, or in veal broth. 

 On the surface of agar it forms a slightly elevated, nearly trans- 

 parent film, and in " stick-cultures " in the same material it grows 

 to a limited extent along the line of the needle, forming a rather 

 nebulous and colourless line, not unlike that produced in the same 

 material by the " bacillus " of rabbit septicaemia. It is distinguished 



Micrococcus Pasteuri from blood of M. Pasteuri from blood of rabbit 



rabbit inoculated subcutaneously with inoculated subcutaneously ■with fresh 

 normal human saliva (Dr. S.). Mag- pneumonic sputum from a patient in 

 nified 1000 diameters. the seventh day of the disease. Same 



amplification as fig. 75. 



from the last-mentioned organism by the fact that it does not kill 

 fowls or pigeons ; by its failure to grow in suitable culture-media 

 at the ordinary room temperature ; and by its morphology. 



Figs. 75 and 76 are from camera lucida drawings, and represent 



