TUE SLIPPER-ANIMALCULE. 



169 



?7^tO 



cv* 



-mm^^- ■ " 



Fig. 87.— Param(xcium caudatum. A, from the left side, showing: the anal spot : 7?, 

 from the ventral side, showing the vestibule en f(xcc; arrows inside the body in- 

 dicate the direction of protoplasmic currents, those outside the direction of 

 water-currents caused by the cilia. 

 an, anal spot; c.r, contractile vacuoles; /c, food-vacuoles ; ic.r, water v;icuoles; m. 

 mouth; mnc, macronucleus; »?iiV', micronucleus; tt', oesophagus : i', vestibule. Thi> 

 anterior end is directed upwards. 



