106 
BULLETIN 106, UNITED STATES NATIONAL MUSEUM. 
only the adaptions to a particular mode of existence in sandy facies. We have 
not observed ovicells on any of our specimens, but we can not affirm their com- 
plete absence before studying a much larger number of specimens and making 
more numerous thin sections. 
OTIONELLA McCALLIEI, new species. 
Plate 12, figs. 1, 2. 
Description . — The zoarium is discoidal, the inner side concave. The zooecia 
are hexagonal, distinct, separated by a furrow, disposed in irregular quincunx lines ; 
the mural rim is thin at the top, enlarged into a cryptocyst below, smooth, sharp at 
the summit. The opesium is elongated, elliptical, bordered by a very small collar. 
The vibraculum is asymmetrical and auriculated, interzooecial, as large as the 
zooecia. On the inner face the zooecia are disposed in radial lines, perforated with 
large pores, communicating with the interior of the zooecia. 
Measurements . — Vibraculum 
\Lv= 0.25-0.30 mm. 
1^=0.12-0.15 mm. 
A-ffinities . — The only specimen found is the figured one, which is remarkable in 
that the ancestrula appears to be double and formed of two large zooecia; this is 
an illusion, for the true ancestrula is by no means placed in the geometric center 
of the zoarium. The ribs of the inner face are arranged in radial lines and are 
independent of the zooecia of the outer face. Nevertheless they ought to com- 
municate with the latter by the tubules, as is the habit in the genus. 
This species differs from Otionella perforata in its much larger vibraculum and 
in the much smaller opesial collar. 
The specific name is in honor of Dr. R. W. McCallie, State geologist of Georgia, 
who has taken an active interest in our work and has furnished numerous specimens 
from his State. 
Occurrence . — Lower Jacksonian: 31- miles southeast of Shell Bluff post office, 
Georgia (very rare). 
Holotype. — Cat. No. 63839, U.S.N.M. 
OTIONELLA PERFORATA Canu and Bassler, 1917. 
Plate 11, figs. 7-19. 
1917. Otionella perforata Canu and Bassler, Synopsis of American Tertiary Cheilostome 
Bryozoa, Bulletin 96, United States National Museum, p. 13, pi. 1. figs. 3, 4. 
Description . — The zoarium is discoidal with a concave inner face. The zooecia 
are ogival in shape, broad, distinct, separated by a furrow, disposed in very irregular 
radial and transverse lines; the mural rim is broad on the sides and below with a 
projecting summit; the opesium is elliptical, little elongated, nearly orbicular, 
bordered by a projecting collar. The vibraculum is as large as the zooecium, unsym- 
metrical and auriculated, rather narrow. On the inner face the radial ribs are 
perforated with numerous pores. There are at least two pairs of large lateral 
septulae to each zooecium, and only one pair in the vibraculum. 
