140 INVERTEBRATA. 



CERIOPORA (REPTONODICAVA) NODOSA, n. sp. 



(Plate vii. fig. 14, a, b.) 

 Ceriopora cavernosa, Catalogue Mus. Practical Geol. 1878, p. 6. 



Description. Polyzoarium massive and irregular, forming large 

 amorphous, globose, and lobose masses ; or pointed processes may 

 also be developed. It is composed of an infinite number of thin 

 superposed layers, which rest in contact one above the other. 

 These layers are not simple and even, but are folded up into 

 domose, mammilated and cylindrical prominences, so that the 

 whole surface is coarsely nodulose. This character is not un- 

 frequently much exaggerated, especially in young specimens, so 

 that the whole structure presents a stunted, domose appearance. 



The under surface is concave and shews a delicate lamellose 

 common plate. 



Cell apertures slightly contracted, rounded or subtriangular. 



Our specimens (Woodw. Mus.) from Upware attain the size of 

 8 x 6 x 4 inches. 



Commonly the surface of the Polypidon is eroded, so that the 

 cell apertures appear large, simple and polygonal. 



Affinities and differences. This species is most nearly allied to 

 Ceriopora mammillosa (Rbmer), from which it differs in its larger 

 growth, and more prominent mammillce ; also the cell openings in 

 Roemer's species are much smaller than in ours: "Ohne Ver- 

 grosserung nicht Sichtbaren" (Romer, Kr. p. 23). Ceriopora 

 (Reptonodicava) cavernosa is a much smaller structure than C. 

 nodosa, with minute cells ; it is well separated from our Upware 

 fossil by the hollow cavernous spaces which are left between the 

 various superposed layers. In C. nodosa the layers are perfectly 

 in contact. In C. spongiosa, Rom., the surface is described as 

 smooth and the pores are round. The general aspect of this 

 massive polyzoon is similar to Zonopora tuberculata, but that 

 species has intermediate pores between the cell's, and the latter 

 have a radiating arrangement. 



Localities. Upware, Brickhill. 



N. Europe. Schoppenstedt, Brunswick. 



