110 BULLETIN 125, UNITED STATES NATIONAL MUSEUM. 



Variations.— The rimule bears two salient condyles on which are supported 

 the small proximal tongue of the operculum. The ovicell is globular, elongated, 

 large; it bears in front a small concavity; it bears small tremopores like the frontal, 

 it is closed by the operculum. 



The large aviculariiun is not median ; it is eccentric and curved. 



The species which Miss Eobertson has figured under the same name appears 

 to be different for the apertura of the ovicelled zooecia is much larger than that 

 of the ordinary zooecia. This is not the case in the figure of Hincks and of our 

 specimen. 



Occurrence. — Pleistocene: Santa Barbara, California (rare). 



Habitat. — Queen Charlotte Islands. 



Plesioty^e.—C&i. No. 68572, U.S.N.M. 



Genus GEMELLIPORELLA Canu and Bassler, 1920. 



1920. Gemelliporella Canu and Bassler, North American Early Tertiary Bryozoa, Bulletin 106, 

 U. S. National Museum, p. 372. 



The ovicell is hyperstomial and deeply embedded in the distal zooecium. 

 The operculum does not close the ovicell and operates in a locella. The form of 

 the apertura is like a keyhole. The frontal is garnished with lateral areolar pores 

 and with a granular pleurocyst. 



Genotype. — Gemelliporella vorax, new species. Range: Pliocene. 



The genus GemeUipora Smitt, 1872, founded solely on the aspect of the apertm^a, 

 is not a natural one. The first species described, G. ehurnea, has been selected by 

 Levinsen, 1909, as the type of the genus and classified in his family Liriozoidae. 

 GemeUipora striatula Smitt, 1872, is a synonym for Trypostega venusta Norman, 1869. 

 GemeUipora glabra Smitt appears to have a smooth frontal, but it is necessary to 

 examine specimens anew. G. limbata Smitt is serial and appears to belong to the 

 Phylactellidae. The keyhole form of the aperture does not appear to furnish a 

 sufficient generic character because it does not corrospond to an important modifica- 

 tion of the hydrostatic function. In establishing the new genus Gemelliporella we 

 have employed the characters furnished by the ovicell and the frontal. 



GEMELLIPORELLA ASPER, rew species. 



Plate 18, figs. 5, 6. 



Description. — The zoarium incrusts oysters. The zooecia are little distinct, 

 irregularly elliptical; the frontal is small, hardly convex, surrounded by large, 

 crowded, areolar pores. The apertura is deep, biu-ied, elongate, shaped like a key- 

 hole, with two lateral symmetrical condyles limiting the rimule; the peristomice 

 is eUi^ptical and bears a little salient mucro. The oviceU is globular, salient, punctate ; 

 its orifice is very large and can not be closed by the opercvdum. On each side of 

 the apertura there are two large orbicular avicularia with pivot, very salient; the 

 one between them is much developed and becomes onychocelliform; its pivot 

 bears a wide rectangular denticle. 



Measurements.-Apert^xrJ^-^^■]l ^°^- Zooeciapr^'^^'^-^^ '^'^■ 



^to =0.10 mm. 1^2 = 0.30 mm. 



Affinities.— The avicularia by then- saliency cover the zoarial surface with a 



great number of asperities which characterize this species, but which render it 



