28 PROCEEDINGS OF THE NATIONAL, MUSEUM vol. ei 



CERIOPORA FALLAX, new species 



Plate 23, figs. 8-10 



Description. — The zoarium is free, subcylindrical, elongated, appar- 

 ently formed of many enveloping lamellae. The tubes are thin; the 

 apertures are polygonal, irregular, with heteroporoid aspect. 



Measurements. — Diameter of large apertures, 0.16 mm.; diameter 

 of small apertures, 0.08-0.12 mm.; diameter of zoarium, 5 mm. 



Structure. — This species is very deceiving. Certain parts of the 

 surface have large and small tubes, as in Eeteropora; but sections 

 do not show mesopores in the strict sense, for here some shorter tubes 

 or others with a smaller diameter may be seen. The lamellae, 



visible exteriorly, are 

 not complete and arise 

 by the development of 

 partial basal lamellae. 



The zooecial walls are 

 vesicular and moniform; 

 the vesicles are little 

 swollen and their lateral 

 walls only are very thick. 

 Diaphragms exist only at 

 the center of the colony. 

 Occurrence . — Lower 



Fig. 13— Cmopora/aZiai, new species. A meridian section, X 16. CrctaceOUS (\ alangian) : 

 Tlie zonal lines are transformed into basal lamellae. Lower Sainte-Croix (Vaud), 

 Cretaceous (Valangian): Sainte-Croix, Switzerland Switzerland (rare) . 



Cotypes.—C&t. No. 69870, U.S.N.M. 



CERIOPORA SPONGIOIDES, new species 



Plate 24, figs. 7-10 



Description. — The zoarium is free, subglobular or massive, with a 

 very narrow base. The tubes are thick ; the apertures are very irrreg- 

 ular and give to the surface the aspect of a calcareous sponge. 



Measurements. — Diameter of orifices, 0.12 mm.; length of zoarium, 

 12 mm.; height of zoarium, 8 mm. 



Affinities. — Our sections were not good and we have been unable 

 to study the structure of this fossil. The species differs from Cerio- 

 pora angustipedes in the aspect of the surface and in its zoaria, which 

 are higher than broad. It differs from Ceriopora ovoidea only in the 

 general aspect of the surface, which is of a nature that may represent 

 only alteration in fossilization. We figure traces of ovicells which 

 are possibly those characteristic of Leiosoecia. 



Occurrence. — Lower Cretaceous (Valangian): Sainte-Croix (Vaud), 

 Switzerland (common). 



Cotype.— Cat. No. 69871, U.S.N.M. 



