NORTH AMERICAN EARLY TERTIARY BRYOZOA. 
129 
curved, finely striated. The opesium is of the same form as the zooecia. The 
avicularium is interzooecial, small, oblique, rounded or pointed; two lateral den- 
ticles indicate the axis of rotation of the mandible. The ovicell is globular, in- 
distinct, smooth, rarely carinated. 
T.J . r~t * fZs=0.50 mm. 
Measurements. — Zooecia , ^ 
|7s=0.2o-0.30 mm. 
Affinities. — The differences between this species and Ellisina ( Reptoflustrella ) 
ovalis D’Orbigny, 1852, are quite insignificant, except that its dimensions are larger 
and the ovicell is almost never carinated. 
It differs from Ellisina ( Semiflustrella ) rhomb oidalis D’Orbigny, 1852, in 
which the micrometric measurements are almost identical although slightly smaller, 
in the much less lozenge shape of the zooecia. 
Ellisina brevis differs from E . laxa. not only in its much smaller dimensions, 
but in its elongated zooecia which are less protuberant in aspect. In these very 
simple forms, the micrometric dimensions are the only constant characters of 
differentiation. 
Occurrence . — Middle Jacksonian: Near Lenuds Ferry, South Carolina (rare) ; 
Eutaw Springs, South Carolina (rare). 
Upper Jacksonian (Ocala limestone) : H miles above Bainbridge, Georgia 
(rare). 
Cotypes . — Cat. Nos. 63896, 63897, U.S.N.M. 
ELLISINA PROFUNDA MacGillivray, 1895. 
Plate 25, fig. 3. 
1895. Membranipora profunda MacGillivray, A Monograph of the Tertiary Polyzoa of Vic- 
toria, Transactions of the Iloyal Society of Victoria, vol. 4, p. 36, pi. 4, fig. 14 ; 
pi. 8, fig. 2. 
1908. Membranipora profunda Canu, Iconographie ties Bryozoaires fossiles de 1’ Argentine, 
Anales del Museo Nacional de Buenos Aires, vol. 17, p. 258, pi. 2, fig. 11. 
The external aspect, the position, the direction of the avicularia, and the micro- 
metric measurements exactly alike, all indicate or appear to indicate the identity 
of the American specimens with Membranipora profunda MacGillivray, 1895. 
However, our unique specimen from near Lenuds Ferry, South Carolina, presents 
a remarkable peculiarity not described by the Australian author and which has not 
been observed on the specimen from Patagonia. In the interior of each zooecium 
there is a kind of double partial mural rim; distally two irregular pores separate 
the two mural rims. This arrangement greatly simulates the structure in the 
interior of the zooecia of Chaperia. The study of this interesting feature remains 
to be made when more numerous specimens have been found. The avicularium is 
sometimes developed in the interior of the distal zooecium. 
0 ccurrence . — Lower Jacksonian (Moodys marl) : Jackson, Mississippi (very 
rare) . 
Middle Jacksonian: Near Lenuds Ferry, South Carolina (very rare). 
55899— 19— Bull. 106 9 
