NORTH AMERICAN EARLY TERTIARY BRYOZOA. 



291 



The zooccium is closed by an opercular valve. The costules are generally 

 closely consolidated together; the lacunae are large and few in number; the lumen 

 more or less distinct. The dietellae are irregular in number (at least three 



- 



lateral pairs) . The ovicell is hyperstomial and is always closed by the operculum. 

 The orifice often has a naucro. The avicularia are dependent. 



Genotype. Cribrilina punctata Gray. 1848. 



Range. Midwayan-Recent. 



O iso 



G -45 



FIG. S3. Genus Cribrilina Gray, 1848. 



A-X. Cribrilina punctata Hnssal, 1841. A-D. Various forms of the species, X 25. (After 

 Hincks, 1880.) E. Ovicell, X 40. The endooecium (olocyst) (cndo) is visible through the 

 broken ectooeciuru ckto. F. Dietellae are seen on the three marginal zooecia, of which the central 

 abnormal one has no aperture, X 55. G. Sagittal section through a zooecium with ovicell. The 

 ovicell is inclosed in a kenozooeciinn (canty), X 55. The distal end of a zooecium with ovicell, 

 from the basal surface. The dietellae of the zooecium and kenozooecium are seen, X 40. I. Die- 

 rellae from the basal surface, X 40. (E-I after Levinsen, 1909.) J. Zooecium seen in profile, 

 X 40: f, septula. K. Ovicell and avicularian cavity, X 40. L-N. Schematic sections through the 

 dietellae, X 35. (J-N after Levinsen, 1894. ) O. Crilriliiia annvlatu Fabricius, 1780. Three bars 

 i if the zooecium of a very simple form, X 150. (After Norman, 1903.) 



CRIBRILINA VERRUCOSA, new species. 



Plate 5, figs. 12-14. 



Description. The zoarium incrusts other bryozoa. The zooecia are distinct, 

 separated by a deep furrow, elongated, elliptical, crenulated on their borders. 

 The cribriform area is convex and formed of large, radial costules; the lacunae 

 are very large, prominent, irregularly placed at the rate of 1 to 2 to each pair 

 of adjacent costules. The aperture is semilunar and is at the bottom of a very 



