250 Transactions of the Society. 



one is placed behind the last two and on the left side. The anal 

 cirri are five in number. The four cirri on the right are long, stout 

 and are placed side by side ; the single one on the left is the 

 smallest of all, and is placed on the right side of the peristome, 

 being separated from others by an interval. The contractile 

 vacuole is posterior. The macrouucleus is bandlike, curved like a 

 bow, and is placed obliquely to the left of the median line. Lt. 

 0214 mm. Br. 0-016 mm. 



Pig. 2. 



Numerous animalcules were observed in the pond water kept 

 in the laboratory for a few days. They were brisk and capable of 

 rapid movements. 



The presence of a small peristome at the posterior end of the 

 body and the absence of marginal cirri are sufficient characteristics 

 for referring the present infusorian to the family Aspidiscidse. 



It differs from the only known genus of the family Aspidiscidee, 

 Ehrbg., in the presence of a row of frontal cirri, well-differentiated 

 from abdominal cirri. 



