ART. 14 CHEILOSTOMATOUS BRYOZOA CANU AND BASSLER 9 



Genus HIPPOTREMA, new genus 



Greek : hippos, horse ; trema, perforation, in reference to the form of the 

 aperture. 



The ovicell is hyperstomial and is not closed by the operculum- 

 The zooecia are piled upon each other in disorder; their frontal is 

 perforated by tremopores. The aperture ii5 formed by a large orbic- 

 ular anter and by a short poster, separatt^d by two cardelles. The 

 operculum does not have lateral linear attachments. 



Genotype. — Hippotremu {Lepralia) janthina Smitt, 1873. Recent 

 This is the Cellepora janthiTia group of Waters of which we have 

 published a text figure (Canu and Bassler, 1920, p. 615, fig. 185). 

 The genus differs from Hippoporidra in the transformation of the 

 pleurocyst into a tremocyst, in the different form of the poster and 

 in the absence of linear attachments to the operculum. 



Family CATENICELLIDAE Busk, 1852 



Genus CRIBRICELLINA, new name 



Proposed to replace Crihricella Levinsen, 1909, preoccupied by 

 Canu, 1902. 



Genotype. — Gatemcella rufa MacGillivray, 1868. Recent. 



Genus CORNUTICELLA, new genus 



The tuberculate imperforate ovicell is at the end of a mother 

 zooecium of a globulus. Vittae. 



Genotype. — CornuticeUa {Catenicella) (?or;mJJa Busk, 1852. Recent. 



Suborder Hexapogona, new suborder. 



Greek : apogonos, descending 



The ancestrula engenders six zooecia regularly erect. 



The families belonging to this suborder of cheilostomatous bryozoa 

 are the Chaperiidae Jullien, 1888, Conescharellinidae Levinsen, 1909, 

 Mamilloporidae, new family and doubtfully the Myriozoumidae 

 Smitt, 1867, and Lekythoporidae MacGillivray, 1882. 



We class here Myriozoum by simple cell analogy, but the ances- 

 trula has not yet been published. Of the Lekythoporidae we know 

 only the ancestrula of the genus Actisecos and we are not certain 

 that the family is a very natural one. 



Family MAMILLOPORIDAE, new family 



Hexapogona with orbicular zoarium without pit. The cells are 

 juxtaposed. The proximal border of the apertura is oriented 



3022—27 2 



