628 
BULLETIN 106, UNITED STATES NATIONAL MUSEUM. 
Affinities. — This species differs from Schizorthosecos interstitia Lea, 1833, in 
the totally different nature of its inner face, which does not bear very numerous 
small pores of tubules. 
Bipora ebumea , Mapleston, 1909, is a recent species bearing pores somewhat 
analogous, but the author has not explained their use. 
Occurrence. — Claibornian (Gosport sand) : Claiborne, Alabama (common). 
Lower Jacksonian (Moodvs marl) : Jackson, Mississippi (rare). 
Cotypes.— Cat. No. 63863,' IJ.S.N.M. 
SCHIZORTHOSECOS RADIATUM, new species. 
Plate IS. figs. 10-19. 
Description. — The zoarium is cupuliform. very little concave. The zooecia are 
indistinct exteriorly, tubular, terminated by a contracted peristomie; before each 
peristomice there are four to 
six small radial costules ; above, 
in the interzooecial angles there 
are two small compensation 
zooeciules or avicularia. The 
apertura is placed at the base 
of the peristomie and has a 
rounde d, distal rimule : the 
peristomice has also a very wide 
and quite variable lower inden- 
tation. On the inner face, the 
radial series are separated by 
lateral mural rims, very thick 
and quite salient; the zooecia 
appear between them in hexagons, smooth, much elongated, little distinct, ter- 
minated by an enormous perforation. 
Affinities. — This species is extremely rare; it is very easily confused with the 
very abundant specimens of the Schizorthosecos interstitia Lea. 1833. To discover 
specimens of it one must study under the microscope the inner face of all the 
specimens found. The enormous salient collars, as well as the small frontal radia- 
tions, well characterize this species. 
Occurrence. — Claibornian (Gosport sand) : Claiborne, Alabama (rare). 
Claibornian (Lisbon formation) : Wautubbee Hills, four miles south of Enter- 
prise. Clarke County, Mississippi (very rare). 
Cotypes. — Cat. No. 6386J-, U.S.N.M. 
Genus ORBITULIPORA Stoliczka, 1861. 
1861. Orbitulipora Stoliczka, Olizocane Bryozoen von Latdorf in Bernburg Sitzungsber- 
iohte cler k. Akademie der Wissenschaften, Wien, vol. 45, Abth. 1, p. 90. 
The apertura is orbicular. The frontal is a tremocyst. The zoarium is or- 
bicular and formed of two lamellae with zooecia back to back. 
B 
Fig. 189. — Genus Orbitulipora Stoliczka, 1861. 
A-G. Orbitulipora petiolus Lonsdale, 1850. Natural size 
and magnified views of a zoarium. (After Reuss, 1867.) 
