36 



ZOOLOO T. 



s 



CD 



m 



CO 1 



cavated a mouth and a throat leading to a so-called stomach 

 or digestive cavity. Two hollows in the body form the con- 

 tractile vesicles, and an- 

 other cavity constitutes 

 the reproductive organ. 

 Prolongations of the body- 

 mass form the cilia, which 

 characterize the Infusoria 

 and give the name to the 

 present order, Ciliata. 

 Paramecium has an elon- 

 gated, oval body "with 

 one end (// ) flattened out 

 broader than the other, 

 and twisted about one 

 third way round, so that 

 the flattened part resem- 

 bles a very long figure 8." 

 In this form, as well as in 

 Stentor (Fig. 25), as Clark 

 remarks, " we have the 

 mouth at the bottom of a 

 broad notch or incurva- 

 tion, and the contractile 



'' HHUnVlMW^^^^H ,/ vesicle on the opposite 



side, next the convex 



Fig. 25. Stentor polymoiyhus, magnified 130 back, whilst the general 

 diameters, expanded and bent slightly over to- ,1 i i v i 



ward the observer; the month i, next the eye, Cavity Of tllC body lies D6- 

 aud the dorsal edge in the distance. , poste- j- wom , fV,a 00 f w -. TVia 

 rior end; sh, the tube enclosing a ; c, the cili- "Wee LWU. 



ated border of the disk (s); v, the larger rigid nrrow -o in flip fio-nrp rpnrp 

 cilia; cv, the contractile vesicle in the extreme ' ul 1J s u 



distance,seen through the whole thickness of the ermf flip rrmvap nf flio iiov 

 body; c>, CT 2 , the posterior prolongation of cv, *~ 



in the distance; ', the circular and radiating tides of illdi^O with which 

 branches of what, by Clark, was supposed to be 



a rudimentary nervous system; n, n 1 , the re- Clark fed lllS Specimens, 

 productive system, extending from the right . 



tide, at n, posteriorly, but toward the eye at w 1 . as tllCV ai'6 whirled 

 -After Clark. J 



along, by the large vibrat- 

 ing cilia (v) of the edge of the disk, against the vestibule of 

 the mouth." During the circuit the food is digested, a 

 mass of rejectamenta is formed near the protuberance, a, 

 which has appeared a short time before. This finally 



cv- 



