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THE BIOLOGY OF HYDRA : 1961 



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Fig. 1. Time of bud initiation in starved Hydra after one feeding. This 

 is a representative experiment on 5 Hydra. Similar results were obtained 

 using hundreds of Hydra. 



stage 12 hours after one meal. Once the bud is initiated, it contin- 

 ues its development through the "medium bud" stage, the "short 

 tentacled bud" stage, and the "long tentacled bud" stage. The gas- 

 trovascular cavity of each bud in the "long tentacled" stage are no 

 longer connected to the parent's cavity, and the buds are now 

 capable of detaching. After its detachment the new bud is then fed 

 until it in turn begins to initiate its own bud. Throughout this entire 

 process we followed the chemical changes occurring in two major 

 phases: bud development initiated by one feeding, and the growth 

 and development of the detached bud to the adult stage. 



The protein, DNA, and RNA values of a six day starved Hydra 

 following a single feeding and during the ensuing stages of bud- 

 ding are shown in Figure 3. It should be emphasized that all DNA 



