ADDITIONAL SPECIES OF 



475. BACILLUS PYOGENES SOLI. 



Obtained by Bolton from garden earth by inoculation into a rat. Found 

 in association with the tetanus bacillus in pus from the inoculation wound. 



Morphology. Closely resembles the bacillus of diphtheria. " It presents 

 the same irregularities of shape, and the transverse, unstained clear spaces 

 in stained preparations, as the diphtheria bacillus. The individual bacilli 

 vary greatly in length and thickness, and many of them are bent and nar- 

 rower through the middle than at the poles." 



Stains readily with the usual aniline colors, but takes the stain irregularly, 

 sometimes showing deeply stained spots which may be perfectly round. Does 

 not stain by Gram's method. 



Biological Characters. An aerobic and facultative anaerobic, non- 

 liquefying, non-motile bacillus. Spore formation not observed with cer- 

 taintyhighly refractive ovoid bodies are sometimes met with, but these do 

 not seem to be specially resistant to heat. In gelatin roll tubes very small, 

 spherical colonies are developed, which under a low power are seen to be 

 finely granular and to have a lemon-yellow color. Grows best in a slightly 

 acid medium very slowly at the room temperature. In gelatin stick cul- 

 tures isolated colonies are formed along the line of puncture. Scanty growth 

 on potato or blood serum. Bolton says : " I have rarely succeeded in getting 

 a growth in agar." 



Pathogenesis. Subcutaneous inoculations in rats, gray mice, rabbits, 

 and usually in white mice produce an abscess at the point of inoculation. 

 Injections into the ear veins of rabbits sometimes give rise to multiple ab- 

 scesses, especially in the joints and kidneys. ' ' The abscesses following sub- 

 cutaneous inoculation form very quickly, within twenty -four hours, and run 

 a longer or shorter course, from forty-eight hours to eight or ten days, 1 in 

 direct proportion to the amount of the culture introduced. The animals do 

 not seem to suffer any inconvenience, as a rule, and after the abscess is 

 opened suppuration ceases. The organism is found aggregated in small and 

 large, irregular clumps in the pus, many of them lying in the pus corpuscles. 

 It seems to form metastatic abscesses only under exceptional circumstances, 

 such as when injected directly into the blood. Otherwise the abscess remains 

 strictly confined to the seat of inoculation in rabbits, white rats, and gray 

 mice." 



476. MICROCOCCUS AQUATILIS INVISIBILIS. 



Obtained by Vaughan from water. 



Morphology. Oval cocci. 



Biological Characters. An aerobic, non-liquefying micrococcus. Grows 

 in the usual culture media at the room temperature, but feebly at 38" C. On 

 gelatin plates deep brown colonies with smooth outline, spreading irregu- 

 larly upon the surface. In gelatin tubes there is a scanty growth along the 

 line of puncture and a spreading growth upon the surface. On agar a thin, 

 white growth. The growth upon potato is invisible. 



Not pathogenic. 



477. BACILLUS GRACILIS ANAEROBIESCENS. 



Obtained by Vaughan from water. 



Morphology. "Bacilli three times as long as broad, often growing into 

 long, slender rods." 



Biological Characters. An aerobic and facultative anaerobic, non- 

 liquefying, actively motile bacillus. Grows rapidly in the usual culture 

 media at the room temperature feebly at 38 C. Upon gelatin plates brown- 

 ish colonies are developed, " spreading irregularly." In gelatin tubes grows 

 abundantly along the line of puncture and also spreads over the surface. On 

 agar a thin, white layer is developed. On potato an abundant and promi- 



