M. K. A. Zittel on Fossil Hexactinellida. 509 



Cephalites, Toulmin Smith (pars)|. 

 Ann. & Mag. Nat. Hist. 1848, pp. 46, 279. 



Like Ventriculites^ but with the upper margin of the funnel 

 truncated, somewhat thickened, and coated with finely porous 

 siliceous membrane. 



•f Cephalites longitudinalis, T. Smith, I. c. pi. xiv. 1. 



fC. ffiUtatus, id. ibid. 2. 



fO. paradoxus, id. ibid. 3. 



Lepidospongia, Rom. 

 Spongit. p. 9. 



External form like Ventriculites ; wall thin, majandrically 

 folded, on the inside with longitudinal furrows. Outer sur- 

 face coated with a dense siliceous membrane, which is inter- 

 rupted by numerous transverse fissures running in a hori- 

 zontal direction. Skeletal structure as in Ventriculites. 



Lepidospongia rugosa, Schliit. Spongitariensch. des Miin- 

 sterl. i. 1-4. 



Family 6. Staurodermidse. 



Cypellia, Pomel (emend. Zitt.). 

 Paleont. de I'Oran, p. 76. 



Top-shaped, basin-shaped, or branched, thick-walled, with- 

 out root. Lattice-tissue irregular ; crossing-nodes with aper- 

 tures or octahedrally perforated. Radial canals generally 

 curved, perforant, with roundish or elongated, irregularly dis- 

 tributed ostia on both sides. Outer surface with large cruci- 

 form sexradiates, of which the outwardly directed arms are 

 aborted. These larger spicules are irregularly cemented to one 

 another by either lamellar or filiform siliceous bridges, or they 

 lie in a perforated siliceous membrane which coats the whole 

 surface. 



Sci/2^hia rugosa, Goldf. iii. 6. 

 [Spongites dohsus, Quenst. p. 671.) 



Staueoderma, Zitt. 



Polyzolc. Funnel- or platter-shaped, spread out above, 

 with a shallow central cavity. Wall thick. On the inner 

 {i. e. upper) surface with numerous apertures of depressed 



X I am acquainted with this genus (which, moreover, is understood 

 here in a much narrower sense than by Toulmin Smith) only from the de- 

 scription and figures. 



