Reproduction and Life-Cycles 



61 



granules is especially striking in Podophrya fixa, which shows the usual 

 ciliated larva and non-ciliated adult of the Suctorea. Basal granules per- 

 sist in the adult, and during reproduction, those in the cortex of the 

 bud multiply and form rows from which the cilia of the larva arise (50a). 

 All the cilia, and apparently their basal granules also, are resorbed in 

 Cyathodinium (164). New infraciliatures appear as endoplasmic units 

 which migrate to opposite surfaces of the body, where cilia then arise from 

 the new basal granules (Fig. 2. 4, D, E). This process resembles the 

 formation of new mastigonts in Lophomonas. 



Budding and schizogony 



In simple budding nuclear division is accompanied by unequal 

 division of the cytoplasm. Budding in ciliates is typically external, while 

 both internal and external budding occur in Suctorea. In internal bud- 

 ding of Tokophrya lemnarum (Fig. 2. 5), a slit-like cavity appears in the 

 endoplasm during division of the micronucleus, and is gradually extended 

 to cut out a spheroidal mass of cytoplasm following division of the macro- 



Fig. 2. 5. Internal budding in Tokophrya lemnarum; tentacles not shown 

 (after Noble). A. Cytoplasmic cleft developing; macronucleus dividing and 

 micronuclear division completed; xl050. B. Completely separated bud en- 

 closed in pouch; ciliary bands developing; x660. C. Expulsion of bud from 

 brood pouch; x660. D. Ciliated larval stage; x715. 



