180 
BULLETIN 125, UNITED STATES NATIONAL MUSEUM. 
Measurements. —Ap er tur a 
Aa = 0.13 mm. 
Za = 0.15 mm. 
Affinities. —The general aspect recalls a little that of Holoporella janihina 
Smitt, 1872. It differs from it in the presence of areolar pores, much scattered, 
and in the presence of the large oral mucro. The oral mucro does not exist on 
the young zooecia. 
Occurrence. —Pleistocene: Mount Hope, Panama Canal Zone (very rare). 
Holotype. —Cat. No. 68710, U.S.N.M. 
Genus SCHISMOPORA MacGillivray, 1888. 
(For description, see Bulletin 106, U. S. National Museum, p. 598.) 
SCHISMOPORA BREVINCISA, new species. 
Plate 32, figs. 11-13. 
Description. —The zoarium incrusts shells. The zooecia are erect and heaped 
at the center and oriented on the margin; the frontal is formed by a granular pleuro- 
cyst surrounded by some large areolar pores. The apertura is oblique, semicircular, 
with a very short, rounded rimule. The interzooecial avicularium is elongate, 
elliptical; its opesium is very large, and its beak is quite rounded. 
Measurements. —Apertura 
ha = 0.15 mm. 
la = 0.16 mm. 
Variations. —The adventitions organs are quite irregular. Besides the large 
interzooecial avicularium without pivot, there are still some much smaller avicularia, 
almost orbicular or somewhat elongate and provided with a pivot. The medium 
umbo is always very short when it exists; it limits then an irregular slit which is 
a false rimule. The marginal zooecia are much elongated and sometimes almost 
cyclindrical. 
Affinities. —This species differs from Discopora verruculata Smitt, 1872, in the 
absence of a transverse avicularium on the frontal. 
Occurrence. —Pliocene (Caloosahatchee marl): Shell Creek, De Soto County, 
Florida (common). 
Cotypes. —Cat. No. 68711, U.S.N.M. 
SCHISMOPORA ABRUPTA, new species. 
Plate 40, figs. 10, 11. 
Description. —The zoarium incrusts shells. The zooecia are indistinct, erect; 
the frontal is smooth and terminated by a mucro very little salient. The apertura 
is semicircular, with a wide rimule short and rounded. The ovicell is deeply 
embedded between the adjacent zooecia; it is transverse, smooth, convex; it is widely 
open in a locella limited by the medium umbo, and it can not be closed by the oper¬ 
culum. There are numerous, small, triangular avicularia with pivot disseminated 
between the apertures. 
. . , [k = 0.15 mm. 
Measurements. —Apertura 7 , _ 
1 [la = 0.15 mm. 
Affinities. —The apertura is rarely visible; it is always deeply embedded at the 
base of a sort of locella. The small avicularia are sometimes more developed; 
they elongate, become lanceolate, and lose their pivot. In spite of the lack of 
precision in its exterior characters this species is not very difficult to determine, 
thanks to the very special appearance of its avicularia. 
Occurrence. —Pleistocene: Santa Barbara, California (rare). 
Cotypes. —Cat. No. 68712, U.S.N.M. 
