Feb., 1920] The Protozoa of Mirror Lake 123 



Vorticella citrina Ehrenberg. 



Several individuals were taken with sediment at Station F 

 on November 7. The cells were hyaline and the pedicle was. 

 about 12 times the length of the zooid. 



Length of the zooid 57)U. 



Vorticella nutans Miiller. 



Several individuals were found in a two weeks old culture 

 of algae taken from a submerged stone at Station G on 

 January 24. 



Length of zooid 64^t. 



Vorticella floridensis Stokes. 



This species was common among algae from the submerged 

 stone (Station G) during February. One occurred late in March 

 in sediment from the stone near the outlet of Mirror Lake 

 (Station K). 



Length of zooid 80-90^1. 



Vorticella elongata Fromentel. 



One individual was taken among algae scraped from the 

 posts (Stations I and I') on March 1. 

 Length of zooid 64/1. 



Vorticella aperta Fromentel. 



One individual was taken among algae scraped from a 

 stone (Station G) late in February. 



Length 64;u; width of peristome 80)u; length of stalk 300/x, 



Vorticella nebulifera Ehrenberg. 



One individual was found in January in algae taken at the 

 point where the spring water enters the larger pond (Station E). 

 This organism was abundant late in February on alga-covered 

 poplar roots from Station D.. 



Length of zooid 72-1 12/^. 



Vorticella utriculus Stokes. 



One individual was taken late in March on alga-covered 

 poplar roots from Station D. 

 Length of zooid 37)u. 



