22 PROCEEDINGS OF THE NATIONAL MUSEUM, vol.61. 



BRACHYSOECIA, new genus. 



Greek. — Brachys, short, in allusion to the slight length of the 

 ovicell. 



The ovicell is longitudinal, very short. The oeciostome is trans- 

 verse, reflexed, adjacent to a tube and of a smaller diameter tKan the 

 peristome. The tubes are expanded with walls somewhat dilated at 

 their extremity. Gemmation is peripheral, regular, around an axial 

 tube. The tubes are closed by a facette (zooecial area) perforated 

 by an orbicular aperture. 



Genotype. — Brachysoecia convexa, new species. Cenomanian. 



This genus differs from Microecia Canu, 1916, in the presence of 

 facettes. It differs from Lohosoecia, new genus in which the aper- 

 ture is also rounded, in the nature of the ovicell and in the absence 

 of salient threads around the facette. 



BRACHYSOECIA CONVEXA, new Bpecies. 



Plate 3, figs. 1-5. 



Description. — The zoarium is free, cylindrical, dichotomously 

 branched, borne on a discoid base. The facettes are hexagonal, elon- 

 gated, separated by a furrow of little depth. The aperture is circu- 

 lar, distal, bordered by a thin salient thread. In section, the tubes 

 are expanded (=funnel-shaped), with walls somewhat dilated at 

 their extremity; gemmation is peripheral, regular, around an axial 

 tube. On the zone of growth the tubes are deprived of facettes. 

 The ovicell is short ; the oeciostome is smaller than a peristome, trans- 

 verse, adjacent to a tube. 



I Diameter of branch 1.6 mm. 



Zooecial diameter .13-0. 16 mm, 

 Distance between apertures .40- .50 mm. 



Structure. — The structure of this species is rather unexpected. 

 The facettes not being bordered as in Melicertites, it was difficult to 

 discover them on the exterior. However they appear clearly in 

 longitudinal sections where also the expanded form of the tubes, 

 their mode of peripheral gemmation and the presence of the axial 

 tube are apparent. The occurrence of an axial tube seems to indi- 

 cate the existence of other, although lamellar, species. In the trans- 

 verse sections this tube appears clearly at the center of the zoarium 

 in the form of a polygonal tube larger than the adjacent ones. 



The occurrence of tubes with facettes is to be noted also in the 

 following families characterized, however, by different ' ovicells ; 

 Melicerititidae and Lobosoeciidae with bordered facettes, Plagio- 

 eciidae with incomplete or rudimentary facettes and the Mecynoecii- 

 dae with the facettes not bordered. 



Occurrence. — Cretaceous (Cenomanian) ; Le Mans (Sarthe), 

 France. 



Gotypes.—Ciinn collection and Cat. No. 68915, U.S.N.M. 



