Plancton 



295 



I 



PLANCTON 



If one draw a net of fine silk bolting-cloth through 

 the clear water of the open lake, where no life is visil Te, 

 he will soon find that the net is straining something out 





Fig. 179. "Water bloom" from the surface of Cayuga 

 Lake. The curving filaments are algae of the genus 

 Anabaena. The stalked animalcules attached to the 

 filaments are Vorticellas. The irregular bodies of 

 small flagellate cells, massed together in soft gelatine, 

 are Uroglenas. 



of the water. If he shake down the contents and lift 

 the net from the water he will see covering its bottom a 

 film of stuff of a pale yellowish green or grayish or bn >wn- 

 ish color, having a more or less fishy smell, and a 

 gelatinous consistency. If he drop a spoonful of this 

 freshly gathered stuff into a glass of clear water and 



