PLATE VIII. 



Figures 1-6. — Leucetta hceckeliana, u. sp. 



Fig. 1. Portion of a horizontal section, 



Fig. 2. Portion of a section through the cortical layer, showing some 



mesoderniic cells and one spermospore, 

 Fig. 3. A cortical triradiate spicule, 

 Fig. 4. A cortical quadriradiate spicule (from the top), . 

 Fig. 5. A regular minute quadriradiate spicule (n, from the top, . 



h, profile view), . . . . x 400 



Fig. 6. A sagittal minute quadriradiate spicule (a, from the top, 



b, profile view), . . . . x 400 



„ 7-10. — Leucetta vera, n. sp. 



Fig. 7. Portion of a horizontal section, . . x 30 

 Fig. 8. Portion of a section through the parenchyma near the inner 



surface, showing large, coarse-grained, pavement cells, . x .300 



Fig. 9. A cortical triradiate spicule, . . x 30 



Fig. 10. A cortical quadriradiate spicule (from the top), . x 30 



