26 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.61. 



The number of specimens bus not permitted us to verify the sec- 

 tions. The aspect of the ovicell is similar to that in the Eleidae, so 

 that the classification of this species is doubtful. 



Occurrence. — Cretaceous (Cenomanian) : Montlouet (Maine-et- 

 Loire), France. 



Holotype. — Canu collection. 



Family PLAGIOECIIDAE Canu, 1918. 



1918. Pl(i</ioecii(lae Canu, Les ovicelles des bryozoaires cyclostomes, Bulle- 

 tin Society Geologique de France, ser. 4, vol. 16, p. 327. — 1920. Canu 

 and Basslek, North American Early Tertiary Bryozoa, Bull, 106, U. S. 

 National Museum, p. 707. 



The longitudinal axis of the ovicell is at right angles to the zooecial 

 axis. The ovicell is formed before the calcification of the neighbor- 

 ing tubes, the formation of which it hinders. The oeciostome is small. 



The genera exhibiting this type of ovicell are Plagioecia Canu, 

 1918, Desmeplagioecia Canu and Bassler. 1920, N otoplagioecia, new 

 genus, Terehellaria Lamouroux, 1821, Cea D'Orbigny, 1852, Latero- 

 cea D'Orbigny, 1852, Stathmefoi'a^ new genus, and Cavaria Hage- 

 now, 1851. 



Genus PLAGIOECIA Canu, 1918. 



1918. Plagioecia Canxt, Les ovicelles des bryozoaires cyclostomes, Bulletin 

 Soci6t6 Geologique de Prance, ser. 4, vol. 4, vol. 16, p. 327. — 1920. Canit 

 and Bassler, North American Early Tertiary Bryozoa, Bull. 106, U. S. 

 National Museum, p. 707, 



The ovicell is a long transverse sack obliterating a certain number 

 of zooecial tubes and developed in the vicinity of the zoarial margins. 

 The oeciostome is small, equal to or less than the zooecial diameter. 

 The tubes are isolated from each other. No adventitious tubes. 



Genotype. — Plagioecia {Tuhulipora) ;?a^ma Lamarck, 1816. 



This genus well exemplifies the variation in methods of growth 

 shown in a group of species all agreeing in their ovicell and zooecial 

 structure. The species we have selected for description illustrate the 

 Berenicea, Discosparsa, MesenteHpora Entalophora., and Reticulipora 

 growths, although all of these same methods may occur in other 

 genera and families. 



PLAGIOECIA VARIANS Ulrich, 1901. 



Plate 3, fig. 12. 



1901. Discosparsa rariatis Ulrich, Maryland Geological Survey, Eocene, 



Bryozoa, p. 20.5, pi. 59, fig. 3. 

 1907. Discosparsa varians Ulrich and Bassler, Geological Survey of New 



Jersey, Paleontology, vol. 4, p. 315, pi. 21, figs. 1, 2. 



Measurements. — Diameter of the peristome 0. 14 mm. 



