1896.] MICROSCOPICAL JOURNAL 89 



glass. In two-and-a-half days the spots were visible to the nak- 

 ed eye, and in three days these had developed into star-shaped 

 colonies-, whitish, and so far without perceptibly liquefying the 

 medium. 



The colonies at first grow from one or two round organisms, 

 which increase irregularly ])y budding. They are about 1-7000 

 in. in diameter, some as large as 1-5000. As soon as these are 

 numerous enough to form a crowded cluster of perhaps 20 to 30, 

 the colony throws out numerous arms of hyaline matter rad- 

 ially, and these keep on increasing in length. Along the arms 

 appear many (say a dozen or two) nuclear spots, not at regular 

 intervals or in regular lines, but here and there, sometimes two 

 or more side by side, and distributed in the direction of the 

 length of the arm. These nuclei grow into round bodies like 

 the parent, and of the same size, then arrange themselves grad- 

 ually in the direction of the length of the arm or ray, and finally, 

 as the medium liquefies, after about five or six days, or less, 

 separate. 



Neither in the resulting nor any other liquid medium have I 

 seen the star-shaped colony. In liquid the organisms divide ir- 

 regularly by fission or external budding, and in a few hours 

 break up into masses of minute spores. This organism is at no 

 time motile, and except in the case of the radial processes above 

 described, retains, as an individual, its rounded form. 



No. 2 " White '' \ These are not visible on the plate for about 



No. 3 "Yellow" f 36 hours. The colonies then appear as white 

 or yellow rounded (sometimes kidney-shaped) spots, which 

 gradually increase in size. In some of them the edge is definitely 

 marked by a surrounding ring of organisms, packed closely 

 and regularly. In others the edge shows no such bounding 

 ring, and is fissured. These do not break up, are not confluent, 

 and consist of masses of extremely minute rounded bodies. On 

 being placed in a liquid medium they multiply rapidly and ir- 

 regularly. 



These two kinds are so similar, except in color, and the dif- 

 ference in color is so slight in the earlier stages of growth, that 

 it is not easy, especially by artificial light, to distinguish theni. 

 They are non-motile, aerobic, and liquefy gelatine but slowly. 



A temporary absence during the growth on the plates when I 



