48 CONNECTICUT GEOL. AND NAT. HIST. SURVEY. [Bull._ 



Fr. sp. ( ?), Fig. 186. Our most common species. 



Fr. sp. (?), Fig. 198. This is a new type of Frontonia, 

 with a body very much flattened, its dorso-ventral diam- 

 eter being less than one-third of its lateral diameter. It is 

 abundant in our waters. 

 Colpoda Miill. 



Laterally compressed, with the dorsal surface rounded 

 and the ventral surface straight. Mouth on the ventral 

 surface one-third of the distance back of the anterior end. 

 Upon the posterior edge of the mouth is a number of long 

 cilia. Multiplication by division into four or more parts 

 in an encysted condition. 



There is a large number of species of this genus found 

 in our waters. Stokes has described many of them. He 

 divides the genus into two, one of which he names Til- 

 lina; but this division is not generally accepted. The spe- 

 cies described by Stokes that I have found, up to the 

 present time, are in the following list : 



C.sp. (?),Fig. 187. 



C. campyla, Fig. 188. 



C. saprophila, Figs. 189 and 190. 



C. sp. (?), Fig. 191. 



C. inUata, Fig. 192. 



C.sp. (?), Fig. 193. 



C. gigas, Figs. 195 and 205. 



C. cucullns O. F. Miill., Fig. 196. 

 Paramecium Miill. 



Elongated, slightly flattened. Rounded at both ends 

 or obliquely truncated in front. Mouth in the middle of 

 the ventral surface or further back, in the bottom of a 

 three-cornered peristome depression, extending toward 

 the left side. Anus ventral between the mouth and the 

 end, or terminal. Ciliation regular; nucleus ellipsoidal, 

 central; secondary nuclei, close by, short and spindle- 

 formed. Numerous trichocysts. 



Par. caiidatum Ehrbg., Fig. 203. 



Par. bursaria Ehrbg., Figs. 201 and 202. 



Par. trichium Stokes, Fig. 206. 



