CYCLOSTOMATOUS BRYOZOA- — CANU AND BASSLER 



63 



Genus THOLOPORA Gregory, 1909 



THOLOPORA VIRGULOSA Gregory, 1909 



Plate 20, fig. 1 

 1909. Tholopora virgulosa Gregory, Catalogue of the Cretaceous Bryozoa in the 

 British Museum, vol. 2, p. 277. (Bibliography, geologic distribution.) 



Our fine specimen corresponds very well to the figures of Goldfuss, 

 1829, and of Simonowitsch, 1871. It differs from the isolated colo- 

 nies of TJiolopora colligata Gregory, 1909, in the smaller diameter of 

 its aperture (0.12 mm. and not 0.20 mm.). 



Occurrence. — Lower Cretaceous (Aptian) : Faringdon, England. 



Plesiotype.—Csit. No. 69912, U.S.N.M. 



Genus RADIOPORA D'Orbigny. 1849 



RADIOPORA TUBERCULATA D'Orbigny, 1850 



Plate 20, figs. 2-5 



1909. Radiopora tuberculata Gregory, Catalogue of the Creta- 

 ceous Bryozoa in the British Museum, vol. 2 p. 288, 

 pi. 4, fig. 8. (Bibliography, geologic distribution.) 



Diameter of the orifices, 0.16-0.20 mm. 



This species is well characterized by the large size of 

 its aperture. The zoarium is formed of many super- 

 posed lamellae of orbicular subcolonies. The study of 

 the inferior face is interesting; it shows that the larva 

 fixes itself on a grain of quartz and that the basal gem- 

 mation operates fan-shaped fashion as in Berenicea. 



Occurrence. — Lower Cretaceous (Aptian) : Faringdon, 

 England. 



Plesiotype.— Cat. No. 69913, U.S.N.M. 



Family LOBOSOECIIDAE Canu and Bassler, 1922 



Genus LOBOSOECIA Canu and Bassler, 1922 



LOBOSOECIA SEMICLAUSA Michelin, 1845 



Plate 14, figs. 12-13 

 1922. Lobosoecia semiclausa Canu and Bassler, Studies on the 



Cyclostomatous Bryozoa, Proceedings U. S. National 

 Museum, vol. 61, p. 81, pi. 12, figs. 4-11. (Bibliog- 

 raphy.) 

 Measurements. — 



Fig. Z2.—Lobos. 

 coeciasemidau- 

 sa Michelin, 1845. 



A. Transverse 

 section, X 18. 



B. Longitudinal 

 section, X 16, at 

 the extremity of 

 a branch. The 

 tubes are wid- 

 ened and have 

 dorsal gemma- 

 tion. Creta- 

 ceous; Lernans. 

 France 



Aperture j^^-O-^S mm.l ^^^^^^^^ |hf = 0.24 (max. 0..30) mm. 

 ^ lla = 0.09 mm. J llf = 0.20 (max. 0.30) mm. 



Diameter of branches, 1 mm. Our specimen from Faringdon shows 

 facettes a little longer than 0.32 by 0.20 mm. If it belongs to this 

 species it should possibly be considered as a variety. 



Occurrence. — Lower Cretaceous (Aptian) : Faringdon, England (very 

 rare) . 



Plesiotype.—Csit. No. 69914, U.S.N.M. 

 53648—26 5 



