56 CONNECTICUT GEOL. AND NAT. HIST. SURVEY. [BulL 



bead-like. Many small secondary nuclei. Anus near the 

 left end of the adoral spiral. The contractile vacuole, 

 lying in the same region, has a long canal reaching to the 

 posterior end of the body. 

 S. ccernleus (?) Ehrbg., Fig. 240. 



S. polymorplius Ehrbg., Fig. 246. Fig. 245 represents the 

 same species, possibly. The species is highly variable. 

 Fig. 245 shows the animal in process of division. 

 Balantidium CI.' & L. 



This is a parasitic genus. Fig 219 found free swim- 

 ming is provisionally referred to this genus. Possibly 

 Bal. coli. 



ORDER HYPOTRICHA. 

 Key to Genera. 



1. Body flattened 2 



Body not flattened 13 



2. Cilia bristle-like, in groups 3 



Ventral side uniformly ciliate except sternum ; a 



group of stronger cilia behind peristome and near 

 posterior end Trichogaster 



3. Many border cilia 4 



Few or no border cilia 12 



4. Ventral cilia many, in rows 5 



Ventral cilia few, rows not evident 10 



5. Ventral cilia all bristle-like, two or more rows 6 



Ventral cilia style-like, sometimes with two addi- 

 tional rows of cilia parallel to right border, or 

 with three such rows of which the inner has only 



a few cilia 9 



6. Five or more longitudinal rows of ventral cilia ; per- 



istome on ventral surface Urostyla* 



Five nearly straight rows of ventral cilia ; peristome 



lateral New genus* 



Six oblique rows of ventral cilia ; body kidney-shaped 



Kerona 

 Two or three rows of oblique cilia ; body elongated in 



front into a neck Stichotricha* 



Two rows of ventral cilia ; body not elongated in 

 front 7 



