4 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 6U 



fourth sections of Membraniporae in our classification of 1920. In 

 addition to these two groups, this new family includes most of the 

 genera of the miscellaneous Membraniporae which we listed in 1920. 

 A discussion of our reasons for including Crihrilina, Acanthocella, 

 and Merribraniporella in this family is given in our unpublished 

 work on the bryozoa of the Gulf of Mexico. 



Division 2. COILOSTEGA Levinsen, 1909 



Family ASPIDOSTOMIDAE Canu, 1908 

 Genus MONOPORELLA Hincks, 1881 



The genus Monoporella was poorly defined and figured by Hincks 

 and its structure was unlaiown until Harmer's work of 1926. In 

 1925 C hrossotoechia was proposed for this type of structure. On 

 Plate 1, figure 2, we illustrate a new species of this generic type. 



Family ARACHNOPUSIIDAE Jullien, 1888 

 Genus EXECHONELLA, new genus 



Greek: exechon, salient, in allusion to the form of the peristomie. 



The frontal pores are orbicular. A peristomie very much devel- 

 oped, surrounds an orifice closed by a true operculum. The ecto- 

 cyst is hidden under the frontal. 



Genotype. — ExechoTvella {Hiantopora) magna MacGillivray, 1895. 



Range. — Eocene (Lutetian) — Kecent. 



Division 3. PSEUDOSTEGA Levinsen, 1909 



Family CELLARIIDAE Hincks, 1880 



Genus CRYPTOSTOMARIA, new genus 



The ovicell is endotoichal, and deprived of any apparent orifice; 

 it is situated at the base of the zooecium where it forms a semicircular 

 convexity. The apertura bears two small lateral indentations; it is 

 deprived of denticles. 



Genotype. — Cryptostoniaria crassatina, new species. Recent. 

 (PI. 1, fig. 5.) 



Genus STOMHYPSELOSARIA, new genus 



Greek : stoma, mouth, hjtpselos, high, elevated, in allusion to the place of 



the apertura. 



The ovicell is endotoichal opening by a wide semicircular orifice 



placed obliquely above the operculum and situated at the base of the 



distal zooecium where it forms a very salient convexity. The a])er- 



