DISTRIBUTION OF FOLLICULINA IN 



377 



By August i much of the Elodea growing in the Elodea zone 

 along shore was black with aggregates of Folliculina. Free 

 swimmers were in the water of the creek in vast numbers : a quart 

 dipped from the surface at random showed in a white bowl from 

 fourteen to one hundred, by actual count, for each quart of water 

 from the surface. By drawing the bowl along the surface, the 

 Folliculina swimming free were concentrated till thousands in a 

 quart made it dark as if sprinkled with black pepper. Though 

 these free-swimming Folliculinas easily escape notice in the 

 greenish water turbid with plankton and sediment, they are 

 readily observed in calm water by an eye near the surface; and 

 standing in water five feet deep one may see them swimming 





FIG. 4. Photograph of two young colonies of free swimmers that have just 

 settled on surface of water in aquarium and formed sacs but no tubes: one individual 

 on extreme left is still in motile form. Preserved specimen, X 20 diam. 



rapidly in all directions, individually in straight and in curved 

 paths. Many deep down in the water were seen best by holding 

 a white object below them, but most of them were near the surface 

 where they congregated especially about any floating object as 

 fallen leaf or floating chip, seemingly influenced by its presence 

 so that they swam toward it. 



While at this time the Folliculina continued to colonize the 

 new growths at tip of the Elodea as fast as it grew so that the 



