336 M, K. A. Zittel on Fossil LitMstidce. 



greed skeletal corpuscles, which interlock with their neighbours 

 and form a membrane-like expansion ; they are smooth on 

 the outer surface, set with small warts on the inner surface. 

 Kecent : Seychelles and English Channel. 



CORALLISTES, O. Schmidt (em. Zitt.). 

 (Atlaut. Sp. p. 22.) 



{Becent.) Sponge cup- or basin-shaped, or bent disciform. 

 Oscula on the upper (inner) surface. Skeletal corpuscles 

 crooked, irregularly branched, with root-like processes at the 

 ends, with knotty warts on the stem and branches. Axial 

 canal following the branches, branched, rather wide, but indis- 

 tinctly bounded, often appearing as if composed of several 

 canals side by side. Both surfaces covered with a layer of 

 forked anchors (PI. VIII. fig. 9) , the prongs of which lie in 

 one plane, while the shaft is directed inwards. For the five 

 living s])ecies of this genus see p. 244. 



Nearly allied to Corallistes are probably the insufficiently 

 characterized genera jEgophymia^ Pumicia^ Cisseliaj ScytJio- 

 phymiaj Pleurcrpliymia^ and Histiodia of Pomel. 



Hetekophymia, Pomel. 



(Pal. de I'Oran, p. 143.) 

 Dactylocahjx, Bow. p. p. 



{Recent.) Sponge fan- or leaf-shaped, undulately folded. 

 Upper surface with large scattered oscula; under surface porous. 

 Skeletal elements as in Corallistes^ but tlie two surfaces with 

 different isolated corpuscles. Under surftice with long-stalked, 

 somewhat bent anchors with short thick prongs, and large 

 bacillar spicules. Upper surface with small, smooth, irregu- 

 larly branching corpuscles. One species. 



Dactylocalyx Jieteroformis^ Bow. Mon. p. 86, pi. iv. figs. 1-4, 

 from China. 



The species bears the name of Goscinosponyia heteroformis^ 

 Val., in the collection of the Jardin des Plantes. Pomel has 

 proposed for the genus -the name of Heterophymia^ as Coscino- 

 spongia comes too near to Goscinopora. Dactylocalyx must be 

 limited to a living Hexactinellid. 



MacAndrewia, Gray. 



(Proc. Zool. Soc. 1859, p. 438, pi. xv.) 



Dactylocalyx p. p., Bow. 

 Corallistes p. p., Schmidt. 



{Recent.) Sponge cup- or basin-shaped or clavate. Inner 



