NO. 2 OSBURN: eastern pacific BRYOZOA — CHEILOSTOMATA 469 



Enantiosula manica Canu and Bassler, 1930. 



Plate 57, fig. 7 



Enantiosula manica Canu and Bassler, 1930:23. 



The zoarium is at first encrusting, but often rises into tapering, 

 finger-like projections to a height of 40 mm or more and 10 mm across 

 the base ; highly multilaminar. The zooecia average about 0.65 mm long 

 by 0.40 mm wide, little distinct; the frontal a coarse tremocyst with 

 large infundibular pores, somewhat costate in full calcification, but 

 without an umbo. The primary aperture is semicircular, the proximal 

 border straight or slightly arcuate; no cardelles, no spines. The oper- 

 culum has the form of the primary aperture and is moderately chitinized, 

 with a narrow bordering sclerite. On either side of the aperture is an 

 avicularium with a long-pointed mandible directed distally and toward 

 the midline, often curved laterally to a slight degree. In addition there 

 is a very minute rounded avicularium, appearing like a large pore, 

 situated in the midline immediately distal to the aperture. I am unable 

 to agree with Canu and Bassler that the avicularia are interzooecial ; 

 their development at the margin of the zoarium shows them to be 

 developed from areolar pores as a part of the zooecium to which they 

 belong, before the succeeding zooecium is formed. This applies also 

 to the minute median avicularium, which is developed from a terminal 

 areolar pore. Dietellae are present in the lateral and terminal walls. 



There are no ovicells. 



The species was described from the Galapagos Islands, Albatross 

 Station D.28 15. 



Hancock Stations: dredged at 24 stations, Albemarle, Chatham, 

 Duncan, Gardner, James, Onslow and South Seymour Islands, Gala- 

 pagos; Secas Islands, Panama; Cocos Island, Costa Rica; Clarion 

 Island, west of Mexico; Carmen and Tiburon Islands, Gulf of Cali- 

 fornia; Magdalena Bay and San Benito Islands, Lower California; 

 and oH Laguna Beach, southern California. The last station, 1130-40, 

 is at the latitude of 33°32'15''N, and the species is distributed from 

 here southward to slightly south of the equator among the Galapagos 

 Islands. The known depth range is from 3 to 60 fms. 



Enantiosula plana new species 

 Plate 57, figs. 8-9 



Zoarium encrusting, white. Zooecia of moderate size, ranging from 

 0.45 to 0.60 mm long by 0.30 to 0.40 mm wide, indistinct. The frontal 

 area is nearly flat, outlined by the areolar pores, a dense tremocyst with 



