176 
BULLETIN 125, UNITED STATES NATIONAL MUSEUM. 
placed in front of the apertura, The apertura is somewhat elliptical, elongated; 
the two small cardelles are placed in the lower third. Around the apertura there 
are four very salient rostra (0.30 to 0.40 mm.) terminated by a small, round avi- 
cularium without pivot. The ovicell is small, convex, not closed by the operculum 
and presents a very fragile orbicular frontal area. 
,, . , f^.a = 0. 17 mm. 
Measurements .—Apertura , _ , . 
r [la =0. 14 mm. 
Affinities .—The present species differs from Holoporella subturrita in its rostra, 
which are free and not attached to the distal zooecium; in its frontal, which is not 
covered with tremopores; and in the presence of cardelles. 
Occurrence .—Miocene (Yorktown formation): York River, Virginia (rare). 
Holotype. —Cat. No. 68699, U.S.N.M. 
HOLOPORELLA SUBTURRITA, new species. 
Plate 25, fig. 9. 
Description .—The zoarium incrusts shells, on which it forms small spinose 
masses. The zooecia are distinct, little erect, swollen; the frontal is convex and 
covered with tremopores. The apertura is elliptical, somewhat elongated, without 
cardelles. It is surrounded by four long rostra terminated by avicularia; the two 
distal rostra have their peduncles attached to the distal zooecium. 
,, , . \ha = 0 . 16 mm. „ . Lz = 0.60-0.80 mm. 
Measurements. —Apertura , _ ,, Zooecia , 
^ [la = 0. 14 mm , [Iz = 0. 36-0. 40 mm. 
Affinities. —With its long rostra this species much resembles Holoporella turrita, 
Smitt, 1872, from which it differs in the two distal rostra attached to the superior 
zooecium, in its tremopores, and in the absence of small nonpedunculate frontal 
avicularia. 
Occurrence. —Miocene (Duplin marl): 28 miles northwest of Wilmington, North 
Carolina (rare). 
Holotype. —Cat. No. 68700, U.S.N.M. 
HOLOPORELLA HEMISPHERICA, new species. 
Plate 3, figs. 9, 10. 
Description .—The zoarium is free, small, hemispherical, about the size of a pea. 
The zooecia are large, distinct, heaped upon one another; the frontal is quite con¬ 
vex, smooth, surrounded by some large areolar pores. The apertura is semi¬ 
elliptical, transverse with a concave proximal border. 
Measurements. —Apertura' 
ha = 0.17 mm. 
la =0.15 mm. 
Affinities .—As we have collected only a few specimens of this small species, it 
is difficult to study its variations’orjts affinities. It appears very well character¬ 
ized by the simplicity of its structure"and the large areolar pores which surround its 
broad frontal. 
Occurrence .—Lower Miocene (Bowden marl): Bowden, Jamaica (rare). 
Cotypes. —Cat. No. 68701, U.S.N.M. 
