PLATE XV. 



FIG. 1. L'tri'iii-iilii/ ifjii'i'!/* !;. A- D. var. biformi* var. n., jj nat. size. p. 14. 

 Fid. 2. Style of same (. X I0o). 

 FIG. 3. Discaster with apical spine ( x 700). 

 FIG. 4. Discaster without apical spine ( X loo) ; 4;; ( x 7oo). 

 FIG. 5. Reduced discaster ( x looj. 



FIGS. C, 7. Reduced discasters from another specimen ( X Ifio). 

 FIG. 8. Suberitfx inifrostoinit* R. & 1). vai 1 . xti'Uatnx. vav. n.. uat. size, p. 19. 

 FIG. 9. Sub-tyle of same ( x loo); 9a ( x 4oo). 

 FIGS. 10, 11, 12. Cortical tyles ( x 100). 



FIG. 13. Surface of S. Micriixtviini* var. .v/c//(///.s, showing stellate poral areas (X ->} 

 FIG. 14. Surface of typical S. iiiirrnxtontux, showing circular pural areas (x io). 

 FIG. 15. Surface of typical S. cciiitinntv* R. & I)., showing stellate poral areas (x 25). 

 FIG. 16. Surface of 6'. caminatus R. & 1>. var. /xijiiUdtus, var. n., showing papillated stellate poral 

 areas (x 25), p. 20. 



