118 llie Ohio Journal of Science [Vol. XX, No. 4, 



Family Stentoridce. 

 Stentor coeruleus Ehrenberg. 



This organism was taken throughout February at Station D, 

 where the collections consisted of algae from a submerged stone. 

 The animals could plainly be seen without a lens. They were 

 common in new collections, but multiplied so rapidly that in a 

 culture two days old, a blue scum, consisting entirely of these 

 organisms, covered the plant material. 



Length of extended animal sometimes as great as 3 mm. 



Stentor polymorphus (MuUer). 



This form was common during the fall in sediment from 

 Station A and on the alga-covered poplar roots (Station D). 

 In March, several individuals were found in algae on the stone 

 near the outlet of the larger pond (Station K) and from sub- 

 merged posts (Stations I and !')• 



Length of the contracted form 226^; extended form SSOyu- 



Stentor roeselii Ehrenberg. 



This form was abundant in collections made from December 

 to the end of March. It was taken among algae from the sub- 

 merged stone (Station G), in algae scraped from posts (Stations 

 I and I'), and among algae growing on the rocks at the point 

 at which the spring water enters the larger pond (Station E). 

 Two individuals were often seen to occupy the same sheath. 



Length of the extended forms 720-1440iu. 



Caenomorpha medusula Perty. 



Several individuals were taken on December 3 among algae 

 from a submerged stone at Station G. One was found on the 

 last day of January at the same place. 



Length 104/^. 



Family Haltcriidce. 

 Strombidium gyrans Stokes. 



This species was common from October 10 until ice covered 

 the lake, when it occurred rarely, but became common again 

 after the thaw late in February. It was taken during the fall 

 in the smaller pond in sediment at Station A, and in January, 

 among algae from the submerged stone at Station G, on the 

 posts (Stations I and I'), in the same material taken from the 



