SENESCENCE AND REJUVENESCENCE 



advanced stage before they separate from the parent body. In 

 such forms the body consists visibly of a chain of zooids in various 



2. 



7.7. 



7.2. 



2. 



38 



7.7.7. 



7. 1. 2. 



7.2. 



\ 



2.7. 



2.2. 



39 



I.I.I. 



7. 1.2. 



1.2. 1. 



1.2.2. 





2.1. I. 



2.1.2. 



o o 



\ / 



2.2. 



FIGS. 37-40. Progress of agamic reproduction in Steno- 

 stomum: the sequence in the formation of new zooids is indi- 

 cated by the numerals. 



40 



stages of development. The development of such a chain of 

 zooids in Stenostomum is shown iri Figs. 37-40. In Fig. 37 only 

 the zooids i and 2 are present; in Fig. 38 zooid i has divided into 



