PLATE XXVII. 



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PAGE 



Figs. 1-13. Hyalonema sieholdi, Gray, . . .190 



Fig. 1. A dried specimen without the Pcdythoa-investment of the Ijasal tuft ; 



Fig. 2. Terminal sieve-plate, outer side view ; natural size. 



Fig. 3. Oxydiact with central thickening and barlis at both ends ; x 300. 



Figs. 4-6. Small amphidiscs of difierent sizes ; x 300. 



Fig. 7. Great amphidisc with knobbed axial beam ; x 300. 



Figs. 8, 9. Middle-sized amphidiscs ; x 300. 



Fig. 10. Oxyhexact with bent echinated rays ; x 300. 



Figs. 11, 12. Autodermal pentact pinules ; x 300. 



Fig. 13. Oxyhexact with straight echinated rays ; x 300. 



Figs. 14-23. Hyalonema gracile, F. E. R, . . 196 



Fig. 14. Longitudinal section of a somewhat damaged specimen, preserved in 

 alcohol ; natural size. 



Figs. 15-17. Small amphidiscs of diSerent sizes ; x 300. 



Fig. 18. Principal triact with rough ends; x 300. 



Fig. 19. Greater amphidisc with echinated axial beam ; x 300. 



Fig. 20. Oxyhexact with straight, smooth rays ; x 300. 



Fig. 21. Autodermal pentact pinulus ; x 300. 



Fig. 22. Autogastral pentact pinulus ; x 300. 



Fig. 23. Oxyhexact with smooth bent rays ; x 300. 



