I 



PARAMCECIUM. 9 



a. The locomotor cilia, which are quite small, and cover 

 nearly the whole of the body. By their vibration the 

 animal is made to move through the water. At the pos- 

 terior end of the body there is a small tuft of much larger 

 cilia (Fig. 2, A;). 



h. Around the edges of the 8-shaped outline of the 

 anterior end, notice a row of much larger cilia. These 

 give rise to currents by which floating particles of food 

 are carried into the mouth, which is situated on the pos- 

 terior bend of the 8. 



III. The surface of the liody is covered by a thin, deli- 

 cate, transparent cuticle, which is rather difficult to see 

 satisfactorily. The cilia are protruded through holes in 

 the cuticle, and if one of the animals be placed upon a 

 slide in a small uncovered drop of water, and watched as 

 the water evaporates, a good view of the cuticle and its 

 perforations may usually be obtained just at the time 

 when the animal begins to dry. 



\X . The body-substance or sarcode. The transparent, 

 somewhat granular, body-substance fills the entire space 

 inside the cuticle, and is pretty' definitely divided into two 

 layers, which are much more distinct and sharply separated 

 than they are in amceba. 



a. The transparent outer la3'er or ectosarc (Fig. 2, Z), 

 which lines the cuticle. 



b. The much more fluid endosarc (Fig. 2, wi), which 

 fills the space inside the ectosarc, and is much more 

 granular. It usually' contains oil-globules, colored par- 

 ticles, and various foreign bodies which are not found in 

 the ectosarc. 



V. Watch a paramoecium push its bod}' into a naiTOW 

 space between the particles of sediment in the water. 

 Notice that the more fluid endosarc is pushed back by the 



