PLATE CI. 



PAGE 



Figs. 1, 2. Scleroplegma conicum, 0. Schmidt, . .351 



Fig. 1. Inner view of a half of a macerated and longitudinally bisected specimen, 

 from a photograph ; natural size. 



Fig. 2. Portion of the macerated dictyonal framework; x 100. 



Figs. .3-8. Margaritdla cceloptychioides, F. E. S., . . 3.51 



Fig. 3. Vertical section of the outer part of the skeleton, with the loose spicules 

 in their natural position ; x 50. 



Fig. 4. Dermal pentact with nodulate rays; x 100. 



Fig. 5. Star-like oxyhexaster with very short principal and long undulating 

 terminal rays ; x 300. 



Fig. 6. Oxyhexaster with long terminal rays ; x 300. 



Fig. 7. Star-like sphserohexaster with a solid spherical centre covering the 

 very short principal rays ; x 300. 



Fig. 8. Small sphserohexaster ; x 300. 



