NO. 3 OSBURN : EASTERN PACIFIC BRYOZOA CYCLOSTOMATA 643 



present on the dorsal sides of the branches and these may fuse with the 

 substratum or with another branch. The dorsal side is more or less 

 striated transversely. 



The zooecia are large, their outlines distinct on the frontal surface; 

 the peristomes curved into an erect position, arranged in fascicles of 

 usually 4 or 5 zoids on either side of the midline, sometimes connate to 

 their tips but often only at their bases. Or they may be entirely free 

 from each other, and there are often isolated peristomes in the midline. 

 The apertures are large, round, averaging about 0.22 mm in diameter. 



The ovicell is a large inflation, usually spread across the whole width 

 of the branch below a bifurcation and frequently continuing on one or 

 both branches ; it surrounds often a large number of isolated peristomes. 

 The ooeciostome is isolated, sub-terminal, moderately short, usually bent 

 distally but it may be tipped in any direction, large, its base wider than 

 a peristome, its tip flared and compressed, as much as 0.60 mm in 

 diameter in the long direction, the pore long elliptical. There is much 

 variation in the form of the pore, which is sometimes round, and the tip 

 of the ooeciostome may be trumpet-shaped without compression. 



This is an extremely common species all along the California coast 

 and I have examined hundreds of specimens, ranging all the way from 

 the short, palmate form to tall, slender branches from sheltered localities 

 and deeper water. It is common in various Pleistocene formations, where 

 it was noted by Conrad, Gabb and Horn, and by Canu and Bassler. I 

 can find no difference between the Pleistocene and recent specimens and 

 I have even found the ooeciostome, which was overlooked by the paleon- 

 tologists, except by Canu and Bassler, 1923:199, who show it in Plate 

 43, fig. 6. 



The Diaperoecia intricata of Canu and Bassler from the Hawaiian 

 Islands is undoubtedly californica, as the differential characters by which 

 they distinguish it are exactly those of californica, "par ses colonies reti- 

 culees, par son grand ooeciostome et par son ovicelle perforce par des 

 tubes ecartes les uns des autres." 



Hincks' description of Tubulipora dawsoni from British Columbia 

 fits the zoarial characters of californica perfectly. He made no mention 

 of the ovicell. 



Hancock Stations: dredged at more than 100 stations and found at 

 shore stations in abundance. The northern limit of its range, as far as 

 known, is British Columbia, including the records of Hincks (Tubuli- 

 pora dawsoni) and O'Donoghue (both Idmonea californica and /. pal- 

 mata.) It is common in the Gulf of California and along the west coast 



