402 WILSON. 



EXPLANATION OF PLATE XXIII. 

 ( Tedanione foetida.) 



Fig. 99. Section of adult — histology of gelatinous tissue. D.4. 



Fig. 100. Dermal membrane. A. 4. 



Fig. 102. Section showing very young egg-cell. D.4. 



Fig. 103. Section showing immature egg surrounded by numerous mesoderm 

 cells. D.4. 



Fig. 104. Section of adult tissue with egg of full size — only one nucleolus. D.4. 



Fig. 105. Section of mature egg — extruded nucleolus. D.4. 



Figs. 1 06-1 10. Sections of segmenting eggs. D.4. 



Fig. III. Section of planula — coarse yolk has disappeared. D.4. 



Fig. 112. Longitudinal section of swimming larva. D.4. 



Fig. 113. Section showing a larva attached to canal-wall of mother. D.4. 



{^Hircinia acuta.) 



Fig. 114. Section of adult tissue with young ovum. D.4. 

 Figs. 115, 115'. Sections showing young ova and follicles. D.4. 



