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THE BIOLOGY OF HYDRA : 1961 



Hydranths 



Frustules 



Medusae 



Fig. 12. Differential utilization of food materials by the three different 

 budding processes at three different feeding rates. The number of buds 

 at each rate is expressed as a percentage of those produced at the next 

 lower rate. 



mediate rate of feeding, but a much smaller increase in the produc- 

 tion of medusa buds (12.5%). Frustule budding was tremendously 

 increased (471.7%). Thus at the different nutritional levels food 

 material was utilized differentially by the three different budding 

 processes as observed also in the previous experiment. 



Hydranth budding appears to limit medusa budding since me- 



