PLATE 2 



EXPLANATION OF FIGURES 



7 Longitudinal section of stem just below a terminal hydranth. Growing 

 egg cells, ov., are present both in ectoderm and in entoderm. The cells in the 

 ectoderm marked a may possibly be primitive egg cells. X 1010. 



8 Longitudinal section of the same stem as previous figure, showing two. egg 

 cells in the entoderm. Other similar cells are found both in ectoderm and in 

 entoderm. X 1010. 



9 Transverse section of stem at junction with the pedicel of a gonophore, 

 showing a large growing egg in the entoderm and a cell, ov., in the ectoderm 

 which is suggestive of the early formation of a primordial germ cell. X 1010. 



10 Growing egg cells from entoderm of stem. Nuclear material is passing 

 into the cytoplasm. X 1765. 



11 Growing egg from the same colony as previous figure. Egg located in 

 the entoderm at the base of the hydranth which bears the gonophores. Promi- 

 nent collection of nuclear material in the cytoplasm near the nucleus; the cyto- 

 plasm is becoming slightly vacuolated. X 1765. 



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