OYCLOSTOMATOUS BRYOZOA CANU AND BASSLEE 



31 



Structure. — ^As in the other Cerioporas from Sainte-Croix, the exte- 

 rior aspect of this species is deceiving, for in longitudinal sections the 

 subcolonies are not complete and have a basal lamella only at the 

 periphery of the colony. There are no zonal lines, as in Ceriopora, 

 but instead imaginary concentric lines (potential) uniting at the 

 basal lamella and marking the zooecial deformations in a manner 

 that each subcolony seems to have a certain autonomy. This differ- 

 ence of structure from Ceriopora justifies the maintenance of the 

 Defranciopora Hamm, 1880. Many of the diaphragms bear two tubes. 

 The. zooecial walls are moniliform and much expanded at their 

 extremity; the vesicles are very small. 



Fig. Id.— Defranciopora neocomiensis , new species. Meridian section through a characteristic specimer» 

 X 16, with potential zonal lines. Lower Cretaceous (Valangian): Sainte-Croix, Switzerland 



Occurrence. — Lower Cretaceous (Valangian): Sainte-Croix (Vaud)^ 

 Switzerland (rare). 



Coty pes. —Cat. No. 69874, U.S.N. M. 



Genus NEUROPORA Bronn, 1825 



1825. Neuropora Bronn. Proposed to replace Chrysaora Lamouroux, preoccu- 

 pied by Pdron. 



The zoarium is free, more or less claviform or arborescent. The 

 suiface is traversed by irregular veinules radiating from a special 

 center. The orifices are ornamented with short visors. The tubes 



