76 BULLETIN 96, UNITED STATES NATIONAL MUSEUM. 



Genus DIPLOTAXIS Reuss, 1867. 



1867. Diplotaxis Reuss, Ueber einige Bryozoen aus dein deutschen Unter- 

 oligocan, Sitzungsberichte der k. Acad, der Wissenschafteii, Wien, 

 Abth. 1 p. 16. 



The zoarium is discoidal and formed of two lamellae back to back. 

 The zoa'cia of the external face are oriented toward the zoarial mar- 

 gins; the zooecia of the inner face are oriented toward the center. 

 The apertiira has a distal rimule. 



Genotype. — Diplotaxis placentula Reuss, 1867. Latdorfian. 



Genus CONESCHARELLINA D'Orbigny, 1851. 



1851. ConeschareUina D'Okbigny, Paleontologle francaise. Terrain Cre- 

 tace, vol. 5, p. 446. 



The zoarium with lunoecia. The zoaria which have the form of a 

 low cone or un arched disk only show a single hijQr of zocecia, 

 Avliile their inner cavity is occupied by numerous avicularia placed 

 in horizontal layers. Ovicells may occur. (After Levinsen, 1909.) 

 The apertura has a distal rimule. 



Genotype. — C onesdiarellma cancellafM Busk, 1852. 



Range. — Mi ocene-Uecent . 



The lunoecia are the openings of special compensation zoceciules. 



Genus BIPORA Whitelegge, 1887. 



1887. Biporn Whitelegge, Notes on some Australian Polyzoa. Proceed- 

 ings Linnean Society, New South Wales (2), vol. 2, p. 337. 



The zoarium with lunoecia. The zoaria are plate-like or fan- 

 shaped with two layers of zocecia ; ovicells are not found. (x\fter 

 Levinsen, 1909.) The apertura has a proximal rimule. 



Genotype. — Bipora u7nbonata Haswell, 1880. Recent. 



Genus FLABELLIPORA D'Orbigny, 1851. 



1851. Flabellipo7'a D'Orbigny, Paleontologie frangaise. Terrain Crfitace, 

 vol. 5, p. 432. 



The zoaria, which have no lunoecia, are plate-like, two-layered ; no 

 ovicells. (After Levinsen, 1909.) The apertura has a proximal 

 rimule. 



Genotype. — Flahellipora elegans D'Orbigny, 1851. Recent. 



Genus MAMILLOPORA Smitt, 1872. 



1872. Mamillopora Smitt, Floridian Bryozoa, pt. 1, Kongl. Svenska Vetens- 

 kaps Akademiens Handlingar, vol. 10, No. 11, p. 33. 



The zoaria, which have no lunoecia, are plate-like, two-layered; no 

 submedian cardelles. There are some avicularia between the zooecia. 

 The ovicelled zooecia are much larger; their apertura is not trans- 

 verse. 



Genotype. — Mamillopora cupula Smitt, 1872. Recent. (Florida.) 



