134 



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 



A\ 



T A 



I.I. 



1.2. 



2. 



A 



A 



I.I.I. 



1. 1.2. 



]5 a^ 



u 



I.I.I. 



k 



1.2. 



2.1. 



■-. r 



» r 



w 



2.2. 



h S 



Figs. 37-40. — Progress of agamic reproduction in Sieno- 

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

 cated by the numerals. 



stages of development. The development of such a chain of 

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

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



1. 1.2. 



I.2.I. 



1.2.2. 



2.I.I. 



2.1.2. 



2.2. 



