The early development of Eucleudrinm. 275 



Explanation of the Figures. 



Plate 14. 



Fig. 1. Long-section of stem of Eudendrium racemosum. eggs 

 in various stages of growth. Gc glandular cells. 



Fig. 2. Long-section of stem of Eudendrium dispar Ag. eggs. 



Fig. 3. Cross-section of stem of Eudendrium tenue Ag. eggs. 



Fig, 4. Long-section of stem of Eudendrium ramosum. Gc glan- 

 dular cells, ec ectoderm, en entoderm, o eggs. 



Fig. 5. Section of gonophore of E. ramosum with contained egg, 

 showing the yolk spheres «/s, nucleus, JV, with wrinkled outline. 



Fig. 6. Section of gonophore showing nucleus in process of mi- 

 gration and apparently devoid of nuclear membrane. 



Fig. 7. Margin of egg in section, showing aggregation of cyto- 

 plasm about the disintegrating nucleus. 



Fig. 8 — 13. Various stages in superficial cleavage of eggs. Figs. 8 

 — 11 sketches of a single eggs within an interval of half an hour. 

 G.J) outline of gonophore. 



Plate 15. 



Fig. 14. Cross-section of egg within gonophore, showing three 

 nuclei near periphery. 



Fig. 15. Section of egg showing yolk balls, and irregularly dis- 

 posed nuclei N, N' position of m;clei in next section of the series. 

 About 300: 1. 



Fig. 16. Section of egg which has passed all phases of surface 

 cleavage, showing superficial aspects of nuclei, together with others 

 within the yolk masses. 250 : 1. 



Fig. 17. Section of egg in stage similar to preceding. 



Fig. 18. Section of egg somewhat further advanced, showing 

 primitive ectoderm ec, and nests of nuclei Nc, together vacuolated 

 condition of superficial cytoplasm. 



Fig. 19. Section of egg at about same stage as preceding, showing 

 something of the cytoplasmic reticulum Rt, at several points. 



Fig. 20. Somewhat different aspects of similar stage in another egg. 



Fig. 21. Partial section, showing in more detail the cytoplasmic 

 reticulum, and chains of nuclei. 520 : 1. 



Zool. Jahrb. XX. Abth. f. Morph. IQ 



