PLATE V. 



Figs. 1-3. Cacospongia levis, n. sp. 

 Fig. 1 . Portion of the skeleton ; natural size. 



Fig. 2. A longitudinal section through it, . . . . . x 4 



Fig. 3. Portion of a section through parenchyma, . . . . x 300 



Figs. 4-6. Coscinoderma altimi, n. sp. 

 Fig. 4. Portion of the skeleton ; natural size. 

 Fig. 5. A transverse section of it, . . . . . . x 4 



Fig. 6. Portion of a section through parenchyma, . . . . x 130 



Figs. 7-9. Carteriospongia radiata, Hyatt. 



Fig. 7. A peripheral segment of the skeleton, . . . . x 4 



Fig. 8. Portion of a section through parenchyma, . . . . x 300 



Fig. 9. A sperm-ball and some mesodermic cellular elements, . . x GOO 



