Plate XXI. 



EJiabdocalyptti.s anijaiculatus Ij. P. 268. 



Fig. 1. The tvpe-.specimeii (Sei. Coll. Rîus, No. 501). l iiatiinil size. 



AH the following figures of .s[)icnlc,s wore taken fronj thi« s[)ceinien. 

 Fig. 2, Two dermal diactins. 300 x . 

 Fig. 3. A gastral hexactin. 300 x . 

 Figs. 4, .5. Thin-rayed oxyhexasters from Ihu i)eri|)liery of the sponge wall. 



300 X. 

 Figs. 6, 7. Stronger-rayed, smooth, hemihexactinose oxyhexasters from the 



gastral side of the sponge wall. 300 x . 

 Fig. 8. Plexactinose oxyhexaster from the same region. 300 x . 

 FiiT. !). Microdiscoliexaster from the dermal membrane. 300 x . 



o 



Fig. 10. A discoctaster. 300 x . 



Fi<ï. 11. Uno;uiculate terminal discs of discoctaster. One in lateral view ; 



two as seen from above. 070 x . 

 Fig. 12. A small fragment from the basidictyonal plate. The small-meshed 



limiting layer and some basidictyonal hexactins in fusion with it 



as well as with one another. 100 x . 



