OBSERVATIONS ON HYDRA 



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nuclei. The chromatin collects round the periphery of the 

 nucleus, leaving the nucleolus in the centre of a clear space 

 (Text-fig. 2, a). The nucleolus sometimes becomes difficult 

 to stain, or only part of its periphery stains. Wager (13) 



Text-fig. 2. 





iif ,. 



b. 



c. 

 Sections of ectoderm showing development of ovum. 



believes that vacuoles form in it at this stage. Secondary 

 nucleoli may make their appearance, often in large numbers. 

 These may be droplets of food material as Wager suggests, 

 for the cytoplasm is also full of darkly staining particles. At 

 a stage just before the definite egg-cell becomes recognizable 



