478 M. K. A. Zittel on Fossil Lithistidce. 



*1. Lymnorea nobilis, Rom. Spong. xv. 1. Cwueert-Planer. 

 *2. Tremospongia grandis^ Rom. ib. xv. 3. Cuvieri- 

 Planer. 



3. Tremospongia Klieni, Gein. Elbth. i. p. 28, pi. iv. fig. 3. 

 Cenomanian. 



Calymmatina, Zitt. 



■^j 



Cnemidium p. p., Scypkia p. p., Mich. 

 Turonia p. p., D'Orb. 



?Pseudosiphonia, Court. 



Sponge compound or simple. Individuals top-shaped, 

 shortly cylindrical or nodular, usually united into stocks by 

 basal amalgamation. Wall thick ; vertex rounded, with 

 a simple central cavity. Base often with processes, thick or 

 narrowed into a stalk. The whole sponge clothed with a 

 dense, smooth or wrinkled, siliceous skin, which, however, is 

 usually rubbed off on the vertex and upper parts of the sides. 

 These rubbed parts are roughened by irregular, short, longitu- 

 dinal and transverse furrows, in the bottom of which are the 

 ostia of simple radial canals, which become finer within. 

 Similar canals run in the opposite direction from without 

 towards the central cavity. Skeleton of two kinds of ele- 

 ments : — 1, rather large quadriradiate Lithistid corpuscles, 

 with strongly branched ends, and gnarled or smooth arms ; 

 2, very small, gnarled irregular corpuscles, which lie in the 

 interstices of the larger elements. At the surface these are 

 very closely packed and form the covering layer. Sometimes 

 the latter contains elegant forked anchors ; and numerous 

 bacillar spicules are scattered in the skeleton and canals. 



This genus is most nearly allied to Turonia^ Mich. The 

 known species are all from the Upper Cretaceous of Tou- 

 raine. 



1. Scyphia sulcataria, var. iriflata, Mich. Ic. xxviii. 4. 

 Senonian. 



Cnemidium crassum, Mich. ib. xxviii. 3. 



*2. Calymmatina rimosa, Zitt. Senonian. 



Scyphia dichotoma, Mich. ib. xxviii. 5 (non Benett). 

 ? 3. Pseudosiphonia tuherculata, Court. Ep. xxviii. 1, 2. 

 Senonian. 



TuRONiAj Mich. 



(Icon. Zooph. p. 125, 1846.) 



Turonifungia, From. 

 Hippatimus p. p., Rom. 

 Turonia, Pom. 



Sponge very irregular, nodular or biconical, the base, the 



