28 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.61. 



PLAGIOECIA COMPRESSA Goldfosg. 1827. 



Plate 5, figs. 1, 2. 



1827. Ceriopora compressa Goldfuss, Petrefacta Gernianiae, Bryozoa, vol. 



1, p. 37, pi. 9, fig. 4. 

 1853. Mesentcripora compressa d'Orbigny, Paleontologle fran^aise, Terrain 



Cretacg, p. 811, pi. 756, figs. 10-13. 

 1899. Diastopora compressa Gregoky, Catalogue of the Cretaceous Bryozoa 



in the British Museum, vol. 1, p. 132. 



We believe this is the species that Pergens has identified incor- 

 rectly with Mesenteripora meandrina Wood, 1856. Gregory has 

 already limited the species to Cretaceous specimens alone. In fact, 

 the ovicell is not of the same nature as that of the specimens from 

 the English Crag and of the recent specimens of the coast of Cali- 

 fornia. 



This species is a typical Plagioeoia. The ovicell is very long and 

 elliptical ; it often results from the fusion of two or three secondary 

 ovicells, and it is not rare to see two or three very small perforations 

 representing the oeciostomes. 



A character which renders the determination of this species easy 

 is the fluting which ornaments the tubes. The zoarium is a Mesen- 

 teHpora; that is to say, a bilamellar zoarium with undulated fronds. 

 It is sometimes multilamellar. 



6>ea^7Tence.— Cretaceous (Neocomian) : St. Croix, Switzerland. 



Cretaceous (Turonian) : Fontaine d'Antoigne, near Chatellerault 

 (Vienne), Les Janieres, St. Calais and Duneau (Sarthe), Liiynes 

 (Loir-et-Cher), and Parnay (Indre-et-Loire), France. 



Cretaceous (Coniacian) : Tours (Indre-et-Loire), Villedieu (I^ir- 

 et-Cher), and Les Phelippeaux (Charente), France. 



Cretaceous (Santonian) : Houssaye and Vendome (Coulommiers). 

 (Loir-et-Cher), and Bedocheau (Charente), France, 



Cretaceous (Maastrichtian) : Maastricht, Holland. 



Cretaceous (Danian) : Moen, Denmark. 



PLAGIOECIA CLYPEIFORMIS D'Orbigny, 1853. 



Plate 3, fig. 11. 



1853. Discosparsa clypeifovmis d'Oebigny, Pal6ontologie franoai-se, Terrain 

 Cretac^, vol. 5, p. 824, pi. 758, figs. 6-9. 



Ovicelled specimens of this species are quite rare. The ovicell 

 is long and thin, salient and parallel to the zoarial margins. The 

 species is rather easy to determine in the French material and 

 D'Orbigny's figure is exact. The zoarium has the Discosparsa form 

 of growth. 



Occurrence. — Cretaceous (Turoniun) : Fontaine d'Antoigne near 

 Chatellerault (Vienne), France. 



