104 
BULLETIN 125, UNITED STATES NATIONAL MUSEUM. 
STYLOPOMA MINUTA, new species. 
Plate 3, fig. 8. 
Description.— The zoarium incrusts shells. The zooecia are distinct, separated 
by deep furrows, elongated, small; the frontal is convex and provided with small 
tremopores. The apertura is small, transverse, semielliptical with a narrow rec¬ 
tangular rimule on the proximal, rectilinear border; the peristome is thin, sharp, 
salient. The ovicell is very large, globular, provided with protuberances and en¬ 
tirely covers the apertura. In the vicinity of the apertura there is a small triangular 
avicularium with pivot, the beak of which is turned obliquely toward the top. 
Measurements. —Apertura 
ha = 0.05 mm. 
la = 0.07 mm. 
Zooecium 
Lz = 0.40-0.45 mm. 
Iz — 0.25—0.30 mm. 
This is the smallest known species of the genus Stylopoma. 
Occurrence. —Miocene (Bowden marl): Bowden, Jamaica (rare). 
Holotype. —Cat. 68556, U.S.N.M. 
Genus SCHIZOPODRELLA Canu and Bassler, 1917. 
(For description, see Bulletin 106, U. S. National Museum, p. 338.) 
SCHIZOPODRELLA ACULEATA, new species. 
Plate 31, figs. 13, 14. 
Description. —The zoarium is massive, very large and formed of many super¬ 
posed lamellae. The zooecia are little distinct, elongated, separated by an irreg¬ 
ular furrow, elliptical or rectangular; the frontal is a tremoc.yst with large, widened 
pores. The apertura is suborbicular and bears a wide, rounded rimule of little 
depth; the peristome is thin, complete and salient on the zooecia of the internal 
lamellae. The ovicell is globular, salient, covered with tremopores. The avic¬ 
ularium with pivot is placed in the vicinity of the apertura; it is very long and 
terminates in a point. 
Measurements. —Apertura 
ho = 0.15 mm. 
lo = 0.12-0.15 mm. 
Zooecia 
Lz = 0.45 mm. 
lz = 0.25 mm. 
Affinities. —This species differs from Schizoporella cumulata Ulrich and Bassler, 
1904, in the length of its avicularium (L = 0.40 mm.). It differs from Schi- 
zopodrella longirostris Hincks, 1886, which also bears a large avicularium, in the 
much greater width of its rimule. When the large avicularium is not much de¬ 
veloped S. aculeata much resembles Stylopoma spongites Pallas, 1766; it differs from 
it in its rimule which is wide and concave and not small and rectangular and also in 
the different form of the ovicell. It differs from Schizopodrella unicornis Johnston, 
1847, in which the apertura is identical, in the presence of a single very large 
avicularium. 
Occurrence. —Pliocene (Waccamaw marl): Waccamaw River, Horry County, 
South Carolina (very rare). 
Cotypes. —Cat. No. 68557, U.S.N.M. 
