NORTH AMERICAN LATER TERTIARY AND QUATERNARY BRYOZOA. 
107 
SCHIZOPODRELLA MARGINATA, new species. 
Plate 30, figs. 4, 5. 
Description. —The zoarium incrusts oysters. The zooecia are distinct, oval, 
wide, bordered by a wide thread, little salient joined to the peristome; the frontal 
is little convex and ornamented with large tremopores. The apertura is orbicular; 
the rimule is wide, of little depth, triangular. The ovicell is little salient, much 
embedded in the distal zooecium with a frontal area. On each side of the apertura 
there are two small round avicularia without pivot. 
Measurements. —Apertura 
7ia = 0.10 mm. 
la = 0.08-0.10 mm. 
Zooecia 
Lz = 0.50 mm. 
lz = 0.28-0.40 mm. 
Affinities. —This small species is quite well characterized and easy to determine. 
It differs from Schizopodrella pusilla, new species, in its great zooecial width and in 
the triangular form of the rimule. 
Occurrence. —Pliocene (Waccamaw marl): Waccamaw River, Horry County, 
South Carolina (rare). 
Holotype. —Cat. No. 68569, U.S.N.M. 
SCHIZOPODRELLA DOVERENSIS Ulrich and Bassler, 1904. 
Plate 18, figs. 1-3. 
1904. Schizopodrella doverensis Ulrich and Bassler, Bryozoa, Geological Survey Maryland, Miocene, 
p. 421, pi. 117, fig. 1. 
Description. —Zoarium a thin sheet on foreign bodies, the figured specimen 
growing on the reverse of Retepora doverensis. Zooecia well distinguished from 
each other but with the surface rather flat; irregularly arranged, though their 
elongate form gives some prominence to the longitudinal rows; average length 
0.6 mm., width 0.35 to 40 mm. Orifice terminal, slightly transverse^ broadly 
notched on the proximal side, on the whole nearly circular. Surface reticulate, 
only slightly convex, the central portion appearing flattened, Avicularia rather 
small, prominent, one on either or both sides of the orifice, rarely wanting, situated 
close to the peristome; apparently both divided by a septum. Ovicells not 
observed. (Ulrich and Bassler.) 
Affinities. —The zooecia are not always regularly oriented. The zoarium 
incrusts shells or other bryozoa. 
This species differs from Schizopodrella unicornis Johnston, 1847, whose aper¬ 
tura is identical, in its larger dimensions and in the absence of the frontal protru- 
berance. It differs from SchizobrachieTla ( Escharella) sanguinea Smitt, 1872, in its 
single very large avicularium and in the smaller and more numerous tremopores. It 
differs from Stylopoma ( Hippothoa ) isabelleana Smitt, 1872, in the place of its 
avicularium not situated below the apertura. 
Occurrence. —Miocene (Choptank formation): Dover bridge, Maryland (rare). 
Pliocene (Caloosahatchee marl): Shell Creek, De Soto County, Florida (very rare). 
Plesiotypes. —Cat. No. 68570, U.S.N.M. 
