SAPBOPHYTIC MICROCOCCI. 221 



original colony there is clear fluid. A low power shows 

 at this stage that the contour of the original colony is 

 no longer quite sharply denned, the ring having an 

 irregular margin and granular surface. In the puncture 

 cultivation the growth and the liquefaction of the gela- 

 tine does not present much that is characteristic. The 

 organism was several times met with in examinations 

 of air. 



Micrococcus radiatus. 



Micrococci under 1 p. in diameter, at times arranged 

 in short chains, more frequently in small masses. 

 Even in 24 hours they form visible colonies ; after two 

 days they are almost 1 mm. in size. They have a white 

 appearance with a yellowish green lustre ; under a low 

 power they are yellowish brown with sharply defined 

 contours, granular, round, or with somewhat irregular 

 borders ; at times they form a series of out-growths, 

 so that they appear like star-fish. In the middle a 

 small remnant of the deeper part of the colony usually 

 persists as a dark centre. At this stage the colonies 

 sink a little into the gelatine, which has become gra- 

 dually somewhat liquid, and after one or two days more 

 a very delicate regularly arranged circle of rays has 

 been formed from the out-growths; from the centre 

 thickly packed delicate threads project with a radial 

 arrangement, and these increase somewhat in breadth 

 towards the periphery, and thus almost run together to 

 form a ring ; a true sharply defined ring is however not 

 formed, but the irregular ends of the rays lie more 

 regularly near one another. After two or three days 

 more a secondary circle of rays has developed from the 

 periphery of the first, and eventually a third is formed ; 

 the radial rays are then however shorter, and the 

 arrangement more irregular. The whole colony occupies 

 at this stage a circle 1 to 1*5 cm. in diameter. 



This organism also grows in a characteristic manner 

 in test tubes, and here also the formation of rays be- 

 comes noticeable. Along the course of the line of ino- 

 culation isolated centres form from which projections 



