CILIOPHORA 



115 



are attached, and these have usually a cuticular stalky which is often 

 expanded at the end to form a shallow cup in which the animal sits or 

 a deep one which encloses it. 



The suctorial tentacles contain a tube, lined by ectoplasm, which 

 opens at the end, where there is often a knob. In some species there 

 are also solid, sticky tentacles, used to capture prey. 



Reproduction by simple binary fission does not occur. In a few cases 

 fission is equal or almost so (Podophrya, Sphaerophrya, Fig. 87 F'), but 

 here one of the products differs from the parent in losing its tentacles 

 and acquiring cilia and thus resembles the buds of other species. This 

 happens whether the parent be a stalked or a floating form. Most 

 species multiply by typical budding. The buds may be external 

 (Fig. 96 B) or formed in brood pouches (Fig. 95) from which they 



Fig. 96. Ephelotagemmipara. After Hertwig. A, Ordinary individual, x 150. 

 B, Budding individual, c.vac. contractile vacuoles ; nu. meganucleus (stained) ; 

 processes of this form the meganuclei of the buds, as in all the budding of 

 the Suctoria (cf. Figs, 87 F', 95). 



escape when they are ripe. External budding is the more primitive, 

 internal the commoner process. In either, one bud or more than one 

 may be formed at a time. The buds (Fig. 87 H), whether external or 

 internal, are usually ciliated and at first without tentacles; the cilia 

 form a girdle round the body, with sometimes the vestige of an adoral 

 wreath. Certain species form also unciliate and often tentaculate oflF- 

 spring by external budding. Some species will, in unfavourable cir- 

 cumstances, resolve practically the whole body into one internal bud 

 which swims away, leaving the pellicle and stalk behind. 



Conjugation is of the same nature as in the Ciliata. Two individuals 

 become united by pseudopodia-like processes of protoplasm, their 

 meganuclei break up, and their micronuclei form pronuclei which 

 unite reciprocally. Often, however, the conjugants do not break 

 apart, but one detaches itself from its stalk to unite permanently with 



