Plate 33. 



Fig. 1. Halitrephes maasi, gen. nov., sp. nov. Tentacle base, showing endodermic roo 



(en.r). X 20. 

 Fig. 2. Halitrephes maasi, tentacle, showing differentiation into proximal and dista 



regions. X 5. 

 Fig. 3. Halitrephes maasi. Somewhat diagrammatic section through bell margin tc 



illustrate relation of endodermal root of the tentacle (en.r) to circular canal 



(c.c) ; (v) velum ; (g) mesogloea. 

 Fig. 4. Halitrephes maasi, oral view of type. The position of .the gonads is indicated 



by the shaded areas at the bases of certain of the radial canals. Slightly 



more than natural size. 

 Fig. 5. Halitrephes maasi. Proximal portion of tentacle in optical section, to show its 



core of chordate endodermic cells ; (en) endoderm core. 

 Fig. 6. Homeonema alba, otocyst. From a photograph. X 250. 



Fig. 7. Halitrephes maasi. Tip of tentacle, closely crowded with nematocysts. X 30. 

 Fig. 8. Halicreas papillosum, otocyst ; (en) endodermic core. From a photograph. X 250. 

 Fig. 9. Halicreas papillosum. Segment of distal portion of tentacle with the ectoderm 



partly stripped off, showing the endodermic core. 

 Fig. 10. Halitrephes maasi, otocyst. x 150. 

 Fig. 11. Homoeouema alba; one octant of bell margin; (en.r) endodermic root of the 



large radial tentacles (t.ra) of which only the stumps persist ; (otc) otocyst. 



There are stumps of fourteen interradial tentacles. From a photograph, x 15. 



