NO. 3 OSBURN : EASTERN PACIFIC BRYOZOA — CYCLOSTOMATA 751 



in his description the presence of a bilabiate aperture, the figure of his 

 specimen strongly suggests the bilabiate type of structure. 



Farrella elongata appears to be well represented in the cooler European 

 waters in the vicinity of England and the Adriatic Sea. 



Hancock Station, 1489-42, Coos County, Oregon; also taken at 

 Tomales Bay, California, by R. J. Menzies. Intertidal. 



Division 5. TerebripoHna Soule, new division 



Ctenostomes with stolonate zoaria that are characteristically imbedded 

 within the calcareous shells of living or dead mollusks, brachiopods, or 

 barnacles, their presence marked by the apertural openings of the zoids 

 appearing at the surface of the shell. The stolons are thin, thread-like, 

 septate. 



The three families that are placed under the Terebriporina cannot 

 be readily differentiated by the pattern of the tracings that appear upon 

 the surface of the shell in which the zoaria are immersed. The only 

 means of postive identification of the families and the genera is examina- 

 tion of zoaria that have been removed from shells by decalcification. 

 The identification of species involves not only the study of zoid anatomy, 

 but serial sections of the autozoids to determine definitely the tentacle 

 number. The family Fenetrantiidae can be anatomically identified by 

 its zoaria with primary and secondary stolons, its typical gonozoids, and 

 the operculated autozoids. Terebriporidae, also with primary and sec- 

 ondary stolons, lacks the operculated autozoids, while Immergentiidae, 

 having autozoids with typical ctenostomatous apertures, has zoaria devoid 

 of true gonozoids, the colonies being composed of a series of zoids joined 

 by stolon-like tubules that are direct extensions of the zoids. 



Family Terebriporidae d'Orbigny, 1847 



Zoaria burrowing, stolonate. The zooecia are connected to the pri- 

 mary or main stolons by means of short secondary stolons emitted from 

 near the distal zooecial extremity. 



Genus TEREBRIPORA d'Orbigny, 1847 



Zoaria stolonate, consisting of primary stolons joined to the zoids by 

 secondary stolons, with the point of union being nearly midway between 

 the distal and proximal extremities, but always closer to the distal end. 

 Polypide provided with a gizzard. Genotype: Terebripora ramosa 

 d'Orbigny, 1847. 



