RABIOPOKA. 
289 
Distribution. 
British : 
Cambridge Greensand : Cambridge. 
? Lower Greensand: TJpware and Farringdon {fide Keeping). 
Foreign : 
Cenomanian : Havre and Cap le Heve, Seine -Inferieure. 
Affinities. 
The list of genera to which this species has been referred shows 
the doubts as to its position. D’Orbigny regarded it as inter- 
mediate between Bomopora and SemimuUicavea. Its large apertures 
and general characters appear to ally it to the Trepostomata rather 
than to the Cancellata, and I am inclined therefore to return it 
to the genus in which d’Orbigny first placed it. 
According to my interpretation of the figures by M. Peron of 
the material referred to this species from the Danian of Chebika, 
in Southern Tunis, that fossil is not a Bryozoan. 
LIST OF SPECIMEjN'S. 
British. 
D. 3159. A small zoarium. Cambridge Greensand. Cambridge. Old Coll. 
Figd. PI. IV. Fig. 8. 
Foreign. 
D. 4394. Three specimens. Cenomanian — Craie cbloritee. Cap de la Heve. 
Presented by AVilliam Hill, Esq., F.G.S. 
25,326. A zoarium, 35 x 32 mm. in diameter and 22 mm. thick. The radial 
lines of apertures are very irregular. Cenomanian. Havre. 
Eamain Coll. 
D. 3715. A zoarium, 21 x 14 mm. in diameter ; the sub-colonies are 6 x 5 mm. 
in diameter and 2-3 mm. thick. Cenomanian. Cap de la Heve. 
Cunnington Coll. 
5. Radiopora inflata, Simonowitsch, 1871. 
Synonymy. 
Radiopora infiata, Simonowitsch, 1871. Bry. Essen. : Verb. nat. Ver. preuss. 
Bheinl. vol. xxviii. p. 38, pi. ii. fig. 1. 
Diagnosis. 
Zoarium small, clavate, with a broad base and narrow peduncle, 
or regularly obconic. The sides may be annulated or smooth. 
Apertures of the zooecia in groups of four, and the radial 
arrangement is imperfectly developed. 
Distribution. 
Cenomanian — Griinsand : Essen. 
u 
