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The Field Naturalist 's Quarterly August 



that the animal has far better control of the cilia than the form we 

 have hitherto studied, for it is able to reverse their motion and so 

 propel itself in any direction at will. The mouth is in a funnel-shaped 

 depression on one side of the body, and lines of long cilia converging 

 to this point carry in food particles. The most interesting feature in 

 Paramcecium, however, is the contractile vacuole, of which it has two, 

 one at each end. It is a compound organ consisting of a central round 

 vacuole, from which radiate several long narrow supplementary vacuoles. 



Fig. 15 



anuihvaitm. 



Fig. 16. — Stylonychia. 



These last slowly fill up with clear fluid, and then apparently discharge 

 their contents into the central vacuole, which in turn collapses in the 

 way described before {F. N. Q., vol. ii. p. 173). 



Stylonychia (the Mussel-Animalcule, Fig. 16) is remarkable for having, 

 in addition to ordinary cilia, a number of long stiff bristles jointed at 

 their junction with the under surface of the body. It can move these 

 independently, and uses them as limbs to walk with. Although these 

 are wonderfully like the limbs of Arthropods (Insects, Crustaceans, etc.), 

 they are, in fact, only modified cilia, and we here see, perhaps, the 

 highest pitch of specialisation to be met with amongst the Protozoa. 



Record of Species Observed. 



