56 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.61. 



1851. Plethopora truncata Hagenow, Die Bryozoen der Maastricliter 



Kreidebilclung, p. 46, pi. 5, fig. 11. 

 1909. Plethopora verrucosa Gkegoky, Catalogue Fossil Bryozoa in British 



Museum, Cretaceous, p. 228 (Bibliography, geologic distribution). 



We have not yet discovered the ovicell of this species and following 

 D'Orbigny, class the genus with Truncatula^ Semicytis, etc. The 

 internal structure will be figured in our next paper. 



Occurrence. — Cretaceous (Maastrichtian) : Maastricht, Holland. 



PLETHOPORELLA, new genus. 



The ovicell is elliptical, elongated, large, little convex, smooth. 

 The tubes are cylindrical, without peristome, with orbicular orifice : 

 their walls are monilif orm ; they are curved at their extremity. The 

 gemmation is peripheral around a bundle of axial tubes. No adven- 

 tious tubes. 



Genotype. — Plethoporella {Plethopora) rammlosa D'Orbigny 1847. 



Range. — Campanian, Maastrichtian. 



Historical. — D'Orbigny was in error in allying the genotype with 

 Plethopora ve'i-rucosa Hagenow, 1851, for the internal structure is 

 quite different since there are no nematopores and the tuberosities 

 which ornament the zoarial surface are not bundles of tubes. Illus- 

 trations of the internal structure of the genotype will be given in 

 our next publication on this subject. 



PLETHOPORELLA RAMULOSA D'Orbigny, 1855. 



Plate 23, figs. 12-lG. 



1855. PletJiopora ramulosa d'Orbigny, Paleontologie Frangaise, Terrain 

 Cretac6, vol. 5, p. 1045, pi. 799, figs. 1-3. 



A full description of this species is reserved for our next publica- 

 tion and we will only remark here that the internal structure is that 

 of Ceriopora where we would have classed the species if we had not 

 discovered the ovicell, which shows its relationship to the Cytisidae. 



Occui^ence. — Cretaceous (Campanian) : Montmoreau, Brossac, 

 Draullard, St. Aulais, Echebrune and Daviat (Charente), France. 



Cretaceous (Maastrichtian) : Royan (Charente inferieure). Manic 

 Eoux and St. Lheurine (Dordogne), France. 



Plesiotypes.—Canu collection and Cat. No. G8980, U.S.N.M. 



Genus OSCULIPORA D'Orbigny, 1849. 



1849. OscuUpora d'Orbigny, Paleontologie frangaise. Terrain Cretac(5, vol. 

 5, p. G. 



The ovicell is globular, limited more or less salient, placed on the 

 frontal or on the dorsal. The tubes are cylindrical, fasciculated, with 

 peristomes in linear fascicles; the gemmation is dorsal in each fas- 

 cicle, and peripheral at the plane of each fascicle. The zoarium has 



