MICROCOCCUS TETRAGENUS COiSrCENTRIOUS 257 



round islets appear, which when inoculation has been exten- 

 sive coalesce with one another, and by confluence of several 



Concentrically stratified 



superficial growtli 



Deep portion of tlie needle-track r^ 



_ Concentric stratification in a fis- 

 sure in the gelatine 



Fict. 92.— Thrust-Oulture is Gelatinb of Micrococcus 



■CETRAGENr.S COXCEN'miCUS, 



a larger roundish compound colony is formed, resembling a 

 holoblastic ovum in process of segmentation. Thrust-cul- 



s 



