NO. 2 OSBURN: eastern pacific BRYOZOA — CHEILOSTOMATA 407 



Smittina cordata, new species 



Plate 48, figs. 1-4 



Zoarium encrusting, usually unilaminar, the surface often irregular. 

 The zooecia are large, 0.65 to 0.85 mm long by 0.40 to 0.55 mm wide, 

 distinct in younger stages, with a raised line in the separating groove ; the 

 frontal is a little inflated, a coarse tremocyst with large pores, the areolar 

 pores usually larger, the frontal granulated in the young but in complete 

 calcification often with irregular umbonate thickenings which occasionally 

 cover nearly all of the frontal area. The primary aperture is subcordate 

 (slightly narrowed distally, but sometimes more nearly round) length 

 0.22 to 0.25 mm, width 0.20 to 0,22 mm, with distinct cardelles and a 

 small but distinct lyrula which is quadrate, or double pointed. The peri- 

 stome is thin, somewhat elevated on the sides, less raised on the distal 

 border and usually wanting entirely on the proximal border above the 

 lyrula, which is always fully exposed. Only rarely there is a small oval 

 suboral avicularium which is not enclosed by the peristome ; frequently 

 whole colonies are without avicularia and when present they are never 

 numerous and never much elevated, but the chamber extends across the 

 front in a narrow lunate cavity proximal to the aperture. 



The ovicell is large, 0.35 to 0.40 mm wide by about 0.30 mm long, 

 thick walled and porous like the frontal. 



The most striking feature of this species is the almost complete absence 

 of the suboral avicularia, always rare and often they are wanting over 

 whole colonies. This character, with the usually low peristome gives the 

 aperture a wide open appearance revealing the whole of the lyrula and 

 the proximal border. Occasionally the peristome rises rather high on the 

 sides and more rarely may be complete proximal to the aperture. 



Type,AHFno. 86. 



Type locality, Catalina Island, southern California, 30 fms. Also 

 at stations 1284-41 and 1410-41, Santa Rosa Island; 1271-41, Anacapa 

 Island; 1232-41 off San Pedro Breakwater; Redondo Beach, and on a 

 shell from an Indian kitchen midden at Dana Point, southern Califor- 

 nia; 1889-49, Cortez Bank and 871-39, Coronado Islands near the United 

 States-Mexican boundary; Dewey Channel off Point San Eugenio, 

 Lower California; and Raza Island, Gulf of Mexico, 28°48'N, n3°W, 

 the most southern locality. Near shore to 40 fms. 



