60 



BULLETIN 125, UNITED STATES NATIONAL MUSEUM. 



are transformed into simple, lateral, irregular sinuosities in S. cupola Tenison Woods, 

 1879; S. concinna Tenison Woods,. 1879; -S. manjinata Tenison Woods, 1879; and 

 S. otwayensis Maplestone, 1904. They are very little visible in S. nitida Maple- 

 stone, 1909, and S . flagellifera Maplestone, 1910. The inner face of all the species 

 is porous except in S. marginata Tenison Woods, 1879. 



Our American species differs from the known forms only in the auriculate form 

 of vibracula. This difference can not form a generic character; first, because the 

 function is the same; second, because porous and cribriform vibracula have been 

 observed in the genus Coscinopleura Marsson, 1885, which belongs to another quite 

 distinct family ; third, because auriform vibracula analogous to those of our species 

 may be observed in the genus Otionella Canu and Bassler, 1917, which does not 

 appear to be opesiulated; fourth, because the large auriform vibracula are pos- 

 sibly porous vibracula which have lost their frontal. There are specimens of Sele- 



"ST 





pt 



Fig. 5. — Genus Seknaria Busk, 1854. 

 A-C. Seknaria aurkularia, new species. 



A. Zoaria, natural size. 



B, C. Noncelluliferous and celluliferous sides, X20. 

 Eocene (Claibornian); Claiborne, Alabama. 



naria maculata in the National Museum Collections provided with analogous auricu- 

 late vibracula. 



Occurrence. — Eocene (Claibornian) Gosport sand: Claiborne, Alabama (rare). 



Cotypes.—Csit. No. 68481, U.S.N.M. 



Family THALAMOPORELLIDAE Levinsen, 1909. 



Genus MANZONELLA JuUien, 1888. 

 1888. Manzonella Jullien, Mission scientifique du Cap Horn, VI, Zoologie, Bryozoaires, p. 79. 

 Opesiules well formed, sometimes multiple. Opesium terminal in the form of 

 an orifice. (After Jullien.) 



Genotype. — Manzonella (Membranipora) exilis Manzoni, 1869, Pliocene. 



