NORTH AMERICAN L.\TER TERTIARY AND QUATERNARY BRYOZOA. 135 



TRYPEMATELLA PAPULIFERA, new species. 



Plate 35, figs.. 12-14. 



Description. — ^The zoarium is free and cylindrical; it incrusts fine algae. The 



zooecia are little distinct, short, wide; the frontal is little convex and perforated 



laterally by large areolar pores. The apertura is semielliptical; the peristome is 



salient and very thin with four distal spines; the ovicell is very large, placed on the 



distal zooecium, globular, salient, closed by the operculum for the passage of the 



eggs; it is costulate and granulated and bears a smooth prominence at its summit. 



On each side of the apertura there is a small round avicularium without pivot. 



Laterally, on the line of the areolar pores, on each side of the zoecium, there is a 



large triangular avicularium, with pivot, transverse or turned toward the top. 



^ , , (?ia = 0.09mm. „ . fi2 = 0.40-0.45 mm. 



Measurements. — Apertura , . ,„ z/ooecia , ^nn n at 



^ lZa = 0.12mm. 1 (2 = 0.30-0.45 mm. 



(With the avicularia.) 



Variations. — This fine species is very irregular in aspect on account of the 



irregularities of calcification. This is very active and gives a great thickness to 



the zooecial walls. The size and number of the avicularia, the organs of oxygenation, 



seem to indicate that the species lived in very calm waters. 



Occwrrence.-'— Pleistocene : Santa Monica (Rustic Canyon), California (rare). 



Cotypes.— Cat. No. 68616, U.S.N.M. 



Group 5. DIVERS GENERA. 



Genus CYCLOCOLPOSA Canu and Bassler, 1920. 



1920. Cyclocolposa Canu and Bassler, Monograph North American Early Tertiary Bryozoa, 

 Bulletin 106, U. S. National Museum, p. 431. 



The apertura is suborbicular or elliptical without cardelles. The frontal is 

 an olocyst, perforated by a double row of areolar pores, and covered by a granular, 

 detachable pleurocyst. The ovicell is hyperstomial, never closed by the operculum, 

 embedded in the distal zooecium. 



Genotype. — Cyclocolposa perforata, new species. 



Range. — Miocene-Pliocene. 



In spite of appearances this genus is very difi'erent from Cyclicopora Hincks, 

 1884. The frontal pores are really areolar pores and not tremopores, for they are 

 separated by short costules; the granulations reveal also the detachable pleurocj'st, 

 moreover, and are often visible on the altered zooecia. In Cyclicopora the opercu- 

 lum always closes the ovicell to assure the passage of the eggs; here this function 

 is assured by the embedding of the ovicell in the distal zooecium, and in the great 

 thickness of the frontal; the orifice is thus arranged in the locclla in front of the 

 tentacular sheath. 



CYCLOCOLPOSA PERFORATA, new species. 



Plate 30, figs. 6-14. 



Description. — The zoarium incrusts oysters over large surfaces. The zooecia 

 are distinct, separated by a furrow, elliptical or hexagonal, short, wide; the frontal 

 is convex, surrounded by a double row of areolar pores, and formed of an oloc3^st 

 supporting a granular and detachable pleurocyst. The apertura is oblique, subor- 



