Chapter 29 

 Subphyliim 2 Ciliophora Doflein 



THE Ciliophora possess cilia which serve as cell-organs of loco- 

 motion and food-capture. In Suctoria the cilia are present 

 only during early developmental stages. The members of this 

 subphylum possess a unique organization not seen in the Plas- 

 modroma; namely, except Protociliata, the Ciliophora contain 

 two kinds of nuclei, the macronucleus and the micronucleus. The 

 former is large and massive, and controls the metabolic activities 

 of the organism, while the latter is minute and usually vesicular 

 or less compact, and is concerned with the reproductive proc- 

 esses. Nutrition is holozoic or parasitic; holophytic in a few 

 forms. Sexual reproduction is mainly by conjugation, and asexual 

 reproduction is by binary fission or budding. The majority are 

 free-living, but a number of parasitic forms also occur. 

 The Ciliophora are divided into two classes : 



Cilia present throughout trophic life Class 1 Ciliata 



Adult with tentacles; cilia only while young 



Class 2 Suctoria (p. 628) 



Class 1 Ciliata Perty 



The class Ciliata includes Protozoa of various habitats and 

 body structures, though all possess cilia or cirri during the trophic 

 stage of life. They inhabit all sorts of fresh and salt water bodies 

 by free-s\^^mming, creeping, or being attached to other objects; 

 some are endozoic in other animals. Free-swimming forms are 

 usually spherical to elliptical, while the creeping forms are, as a 

 rule, flattened or compressed. 



The cilia are extremely fine, comparatively short, and as a rule 

 arranged in rows. In some forms they diminish in number and 

 are replaced by cirri. The cilia are primarily cell-organs of loco- 

 motion, but secondarily through their movements bring the food 

 matter into the cytostome. Moreover, certain cilia appear to be 

 tactile organellae. The food of free-living ciliates consists of 

 small plant and animal organisms which ordinarily abound in the 

 water; thus their nutrition is holozoic. The ciliates vary in size 

 from less than lO^t up to 2 mm. in large forms (as in an extended 



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