NO. 2 OSBURN: eastern pacific BRYOZOA CHEILOSTOMATA 365 



Type, AHF no. 76. 



Type locality, Hancock Station 1340-41, Tanner Bank, off San 

 Diego, California, 32°41'00''N, 119°06'30''W, at 38 fms. Also at 

 Station 1896-49, Tanner Bank, 22 fms; and 1196, Cortez Bank, 32° 

 35'00''N, 119°ir45"W, at 110 fms. 



Genus HIPPOMONAVELLA Bassler, 1934 



"The ovicell is hyperstomial. The frontal is a pleurocyst surrounded 

 by a row of areolar pores. The aperture bears two cardelles more or less 

 median. In front of the aperture there is an oral avicularium placed on 

 the median axis of the zooecium. Genotype, Lepralia praeclara Mac- 

 Gillivray, 1895." Bassler, 1934:407. 



It should be added that the ovicell is closed by the operculum, and 

 that more often than not the avicularium is off center and frequently 

 at the side of the aperture with all intermediate positions represented. 

 The operculum is well chitinized, yellowish in color. 



Apparently the genus has not been recognized except as a fossil, but 

 two living species, Schizoporella longirostrata Hincks, 1883, and Hippo- 

 menella parvicapitata Canu and Bassler, 1930, are modern representa- 

 tives. 



Hippomonavella longirostrata (Hincks), 1883 

 Plate 43, figs. 1-3 



Schizoporella longirostrata Hincks, 1883:477. 

 Schizoporella longirostrata, Robertson, 1908:291. 

 Schizoporella longirostrata, O'Donoghue, 1923:36. 

 Schizomavella longirostrata, Canu and Bassler, 1923:109. 

 Schizomavella longirostrata, O'Donoghue, 1925:102; 1926:59. 



Zoarium encrusting on shells and stems, the thick ectocyst gray or 

 light brown. Zooecia moderate in size, 0.45 to 0.65 mm long by 0.30 

 to 0.40 mm wide, distinct, slightly inflated, rather regularly arranged 

 in radiating lines. The frontal is a granular pleurocyst with a row of 

 areolar pores and usually with 2 or 3 additional rows ; sometimes most 

 of the frontal is perforated, but the central area is always imperforate. 

 The primary aperture (about 0.15 mm in either dimension) is rounded 

 distally, straight on the sides, and the poster extends the full width 

 behind the strong cardelles with a broad shallow sinus; as pointed out 

 in Hincks' original description, there is considerable variation in the 

 form of the poster. The operculum is well chitinzed, light brown in 



