NO. 3 OSBURN : EASTERN PACIFIC BRYOZOA CYCLOSTOMATA 675 



3. Sterile internodes of 1 to 3 zooecia, fertile ones of 3 to 5; 



ovicell adnate for its whole length and its ooeciostome 



terminal Filicrisia 



Internodes of 3 to many zooecia, usually 5 or more except at 

 the base ; ovicell adnate for its entire length, the ooeciostome 

 more or less terminal 4 



4. Internodes with 2 alternating series of zooecia ; ovicell promi- 



nent, expanded dorso-ventrally Crisia 



Internodes with 2 to 8 or more zooecia in cross-section, not 

 regularly arranged; ovicell expanded laterally between the 

 tubules Crisulipora 



Genus GRISIDIA Milne-Edwards, 1838 

 Genotype, Sertularia cornuta Linnaeus, 1758. 



Grisidia cornuta (Linnaeus), 1758. 

 Plate 71, fig. 1 



Sertularia cornuta Linnaeus 1758:810. 

 Crisia cornuta, Hincks, 1884:203. 

 Crisia cornuta, O'Donoghue, 1923:7. 

 Crisidia cornuta, O'Donoghue, 1926:18. 

 Crisidia cornuta, Borg, 1926:260 and 349. 



The zoarium is delicate, branching dichotomously, each branch con- 

 sisting of a single series of zooecia, each zooecium constituting an inter- 

 node. The zooecium is slender, elongate (0.60 to 0.80 mm long), dis- 

 tinctly arcuate ; the succeeding zooecium arises on the dorsal side toward 

 the distal end, paired when branching. Long filiform processes (1.0 

 mm or longer) often arise beside the zooecial base, jointed at the base 

 and usually twice more; from their position and mode of origin these 

 processes would seem to be vestigial zooecia; at any rate they are not 

 homologous with the spines of other bryozoan orders. 



The ovicell is a gonozoid, free with a terminal ooeciostome, and rep- 

 resents an internode ; it never bears a spinous process. 



Hincks and O'Donoghue have listed this species from several localities 

 in British Columbia waters; otherwise it has not been noticed previously 

 on the Pacific coast. 



Hancock Stations: 1269-41, off Anacapa Island, at 41 fms; 1279-41, 

 off San Miguel Island, at 40 fms; and 2042-51, off Long Beach Light, 

 at 14 fms; all from southern California. Also off Pescadero Point, 

 outside of Monterey Bay, California, A. E. Blagg, collector. 



