PLATE V. 



Fi);s. I — 4 Ragadinia annulata n. sp. Different forms of single 



and combined skeleton spicules. Fig. 3. shows two 

 of the spicules attached together *^ .... 58 



Figs. J — 8 Racodiscula and allied genera. Detached and com- 



bined skeleton spicules. Fig. 7 shows a portion of 

 the skeleton with the spicules naturally attached 

 together *? ■ • • • • .60 



Figs, g, JO, loa, 11 Stauractinella cretacea n. sp. Free skeletal spicules 70 

 Hyalostelia fusiformis. Free skeletal spicules 71 



Leptophragma, sp. Fragment of the skeletal mesh 65 



Leptophragma, sp. Skeletal mesh with solid nodes 66 

 Craticularia sp. Skeletal mesh with solid nodes 66 



Cystispongia sp. Skeletal mesh with solid spherical nodes 67 

 The same. .Surface layer of the skeletal mesh . 67 



Coscinopora, sp. Fragment of the skeletal mesh with 



lantern nodes ... 68 



The same. Portion of the outer membrane . 68 



The same. Fragment of the root-fibres . 68 



Ventriculites? sp. Portion of the surface membrane. 69 

 The same. Fragment of skeletal mesh with lantern 

 nodes . . , . . 69 



Spined shaft of anchoring spicule of Hexactinellid 

 sponge ... . ... .72 



Spicules showing irregular tubes or borings in their 

 interior ^^ . . . . . . . 73 



Trifid spicule, showing infiltration of the inner por- 

 tion of the spicule, as well as of the canal ... 14 



Figs. I — 8, 28, 2g are drawn to the scale of 40 diameters the rest 

 of the figures are on the same scale of 20 dia- 

 meters. All are drawn by means of the Camera lucipa. 



