226 



DEPARTMENT OF THE XATAL SERTICE 



8 GEORGE V, A. 1918 



liquefies serum slightly and subsequent to coagulating milk digests the clot. This 

 organism was later found by Birge."''^ It is in the two last characteristics that I find 

 the close resemblance to M. zymogenes noted above. The original description of Str. 

 gracilis of Escherich cited by Winslow ^'^ includes non-liquefaction of blood serum 

 and failure to coagulate milk; but summing up the variations Winslow provisionally 

 defines his " type centre " Str. gracilis as follows : Small coccus, appearing in chains, 

 ferments lactose and coagulates milk, may ferment mannite and salicin, liquefies 

 gelatine actively. 



While the organism I have described appears to have certain particular character- 

 istics, I hesitate to depart from WinsloVs view regarding the relationship of the 

 variants in his tentative group of streptococcus liquefiers ^^. I conclude therefore 

 that this organism which culturally and biochemically is identical with the M. zymo- 

 genes of MaeCallum and Hastings ^^ should be placed as a variety of the type Str. 

 gracilis. 



SUMMARY AND COIs^CLUSIONS. 



1. Three strains of bacteria have been isolated from the destroyed tissue of cope- 

 pods which had died in culture flasks. 



2. Summarized, the biological features are as follows : — 



Gi'ain's Stain 



Spores .... 



Cap.'inle 



Motility 



Agar. 



Gelatine 



Pfttato 



Liietfier's Blood Serum. 



Milk 



Thermal death pt 



Optimum temperature. 



Luxuriant . . . 

 No liquef . . . . 

 Abundant . . 

 No digestion 

 Coagulag .... 



tJO°C 



37°C' 



II. Rod -form. 



+ 

 Moderate . . 

 No liquef. . . . 

 Moderate . . . . 

 No digestion . 

 No change 



55 



37 C 



III. Coccus. 



+ 



+ 



Scant. 



Liquef. 



Scant. 



Slight digest. 



Coag. and digest 



60°0. 



37°0. 



-j- = acid. -)-+ = acid and gas. 



