MEMBEANIPOR A . 213 



but sometimes there is only one. The aperture is oval. They are 

 medium in size. 



FIG. 21. Membranipora jurassica, FIG. 22. Onychocella flabelliformis 

 Gregory. (Lamx.). 



Dimensions. Length of a zooecium l'3mm. ; breadth 0'85 mm. 



Distribution. Bathonian Calcaire polypiers : Kanville, France. 



Type. Brit. Mus. D. 180. 



Affinities of the species. This species belongs to a group which 

 is well represented in the Cretaceous, and it is advisable to 

 compare it with the following seven species. From Membranipora 

 lipunctata (Goldf.) l it differs in that in the latter the aperture 

 is oval, the zooecia are less regular, and there is but one 

 avicularium ; the species are allied in general aspect and the 

 structure of the rim. M. velamen (Goldf.) 2 resembles the new 

 species in the shape of the aperture, but it has a more extensive 

 front wall, larger (and possibly vicarious) avicularia, and the shape 

 of the zocecia is different. M. cypris, D'Orb., 3 agrees in the 



1 CeUepora bipunctata, Goldfuss, Petref. Germ. Bd. i. Ht. 1, 1827, p. 27, 

 pi. ix. fig. 7 ; and Hagenow, Die Bryozoen der Maastrichter Kreidebildung, 

 1851, p. 76, pi. ix. fig. 9. 



2 Cellepora velamen, Goldfuss, op. cit. p. 26, pi. ix. fig. 4 ; and Hagenow, 

 op. cit. p. 97, pi. xii. fig. 1, in which the type is refigured. 



3 Pal. fran9. Terr. cret. t. v. p. 551, pi. Dcvii. figs. 11, 12. 



Flustrina regularis, D'Orb., ibid. p. 306, pi. occii. figs. 17, 19. Flustrina 

 elegans y p. 302, pi. Dcci. figs. 17-19, appears to be only a worn variety of this 

 species. 



