58 OASPEE 0. MILLER. 



the next morning ; in others not until near the middle of the 

 day. 



In one observation by the writer, the plasmodium lying on 

 the hay at the surface of the water began about noon to crawl 

 up the side of the flask. By 6 p.m. the plasmodium had 

 collected at the point where the sporangia formed ; by 7 p.m. 

 the branches were drawn in, and the surface was covered by a 

 number of hemispherical projections ; and by 6 a.m. the 

 following day the sporangia were fully formed. In other 

 cultures observed the plasmodia were resting at the surface of 

 the water at 6 p.m.; by 9 o'clock the next morning they were 

 out of the water, and the sporangia had begun to assume a 

 cylindrical shape. By 11 a.m. the shape of the sporangia 

 was fully developed ; the colour appeared first in the base 

 of the columella, gradually going to the apex. By 2 p.m. 

 the sporangia were of a brownish-red colour except at the 

 apex, which was yet a yellowish-white on tiie surface. By 

 5 p.m. the colour was fully developed and the sporangia were 

 completed. 



Tiie sporangia of Phys. cinereum, so far as observed, 

 began to be developed at 3 — 6 p.m., and were completed by 

 the next morning. The sporangia of Chond. diff., Didym. 

 microcarpon, and Didym. farinaceum also developed for 

 the most part at night. 



Observations and Speculations concerning the 

 Formation and Growth of the Plasmodia. 



In his first studies De Bary failed to show how the plasmodia 

 develop, whether by growth from a single zoospore or by the 

 fusion of a number of zoospores. 



Cienkowski (6, 7) described and pictured the fusion of 

 the zoospores to form small plasmodia, and he saw plasmodia 

 which had later taken in foreign particles, spores, and micro- 

 cysts. 



De Bary (8, 21) accepted Cienkowski's results, although 

 he never saw the zoospores fuse. 



Ward (25) , in speaking of the fusion of the zoospores to 



