402 WILSON. 
EXPLANATION OF PLATE XXIII. 
(Tedanione foetida.) 
Fic. 99. Section of adult — histology of gelatinous tissue. D.4. 
Fic. too. Dermal membrane. A.4. 
Fic. 102. Section showing very young egg-cell. D.4. 
FIG. 103. Section showing immature egg surrounded by numerous mesoderm 
cells. D.4. 
Fic. 104. Section of adult tissue with egg of full size— only one nucleolus. D.4. 
Fic. 105. Section of mature egg — extruded nucleolus. D.4. 
Fics. 106-110. Sections of segmenting eggs. D.4. 
Fic. 111. Section of planula — coarse yolk has disappeared. D.4. 
Fic. 112. Longitudinal section of swimming larva. D.4. 
Fic. 113. Section showing a larva attached to canal-wall of mother. D.4. 
(Wircinia acuta.) 
Fic. 114. Section of adult tissue with young ovum. D.4. 
Fics. 115, 115’. Sections showing young ova and follicles. D.4. 
