NORTH AMERICAN LATER TERTIARY AND QUATERNARY BRYOZOA. 
25 
The species may perhaps be confused with Callopora dumerilli Savigny-Au- 
douin, 1826, in which the exterior aspect is quite similar; it differs from it in the 
presence of nodules instead of avicularia placed on the gymnocyst (and not between 
the opesia). 
Occurrence .—Lower Miocene (Bowden marl): Bowden, Jamaica (rare). 
Habitat .—Florida (Hincks). 
Plesiotypes. —Cat. No. 68410, U.S.N.M. 
MEMBRANIPORINA BACCATA, new species. 
Plate 9, fig. 14. 
Description .—The zoarium is incrusting, unilamellar. The zooecia are distinct, 
separated by a deep furrow, much elongated, elliptical or irregular. The mural rim 
is thin, regular, salient, rounded, covered with large granules. The opesium has 
the same form as the zooecium. 
,, J „ f ho = 0.50 mm. 
Measurements .—Opesia j ^ _ 99 
mm. 
Zooecia 
Lz = 0.60 mm. 
Iz =0.35 mm. 
Variations .—The zooecia giving rise to new series are much larger; they are 
numerous, and when the zoarium is not perfectly regular the smaller zooecia which 
they emit have not sufficient place for development and thus become deformed. 
We have noted traces of spicules, so that this species could possibly belong to 
the genus Acanthodesia. However, it is imprudent to pronounce on this point 
from a single specimen. The epsemble of the large granules of the mural rims give 
to this species the aspect of a chain of pearls. 
Occurrence .—Miocene (St. Mary’s formation): Bowler’s wharf, 18 miles above 
Urbana, Middlesex County, Virginia (rare). 
Holotype. —Cat. No. 68411, U.S.N.M. 
MEMBRANIPORINA CALIFORNICA Gabb and Horn, 1862. 
Plate 33, fig. 6. 
1862. Membranipgra californica Gabb and Horn, Monograph Polyzoa Secondary and Tertiary 
formations of North America, Journal Academy Natural Sciences of Philadelphia, ser. 2, 
vol. 5, p. 160, pi. 20, fig. 46. 
The original description is as follows: 
Colony encrusting, cellules arranged in lines, not always in regular quincunx. Cellules pyriform, 
sometimes continued behind, often abruptly truncated. Opening large, occupying two-thirds or more 
of the cellules; varying from rounded triangular to oval, usually narrowest in front, never sharply acumi¬ 
nate. Surface sometimes rounded about the oval opening, at others carinate, midway between the 
aperture and the margin of the cellule, from which line the surface slopes downwards, convexly in 
both directions. Behind the opening the surface is convex, often narrow. No abortive cellules nor 
ovarian vescicles were observed. 
We have been unable to find specimens of this species and we therefore repro¬ 
duce the original description and figures for the benefit of future students. 
Occurrence. —Pleistocene: Santa Barbara, California. 
12184—23—Bull. 125-3 
