NORTH AMERICAN EARLY TERTIARY BRYOZOA. 
519 
in the genotype. However we have not yet concluded that they are absent, as in 
such small zoaria they are fragile. One of the sections taken through the zoarial 
apophyses shows that these are hollow ; we are absolutely ignorant of their use. for 
we have no analogous case in the recent species. 
Affinities . — This species is easy to differentiate from Semihasioellia tripora / 
its small peristomial pores are much smaller and hardly visible; its zooecial length 
is larger (more than 0.40 mm.) ; the zoarial apophyses are smaller. 
Occurrence. — Jacksonian (Zeuglodon zone) : Cocoa post office, Choctaw County, 
Alabama (very rare). 
Upper Jacksonian (Ocala limestone) : Chipola River, east of Marianna. 
Florida (rare) ; Old Factory, about 14 miles above Bainbridge, Georgia (rare). 
Vicksburgian (Marianna limestone) : West bank of Conecuh River, Escambia 
County, Alabama (very common) ; 
24 miles north of Millrv, Washington 
County, Alabama. 
Cotypes. — Cat. No. 04166, U.S.N.M. 
SEMIHASWELLIA (?) CLARA, new species. 
Plate 66, figs. 28, 29. 
Description. — The zoarium is free, 
a little compressed, formed of three 
rows of zooecia disposed on only one 
Fig. 152. — Genus Gigantopora Ridley. 1881. 
A-E. Gigantopora lyncoides Ridley, 1881. A, B. 
Zooecia, seen from the front and in profile. (After 
Ridley, 1881.) C. Young zooecium. D. Normal zooe- 
cium. E. Operculum. (C-E after Kirkpatrick, 1888.) 
the frontal is convex and ornamented 
with some tremopores irregularly disseminated. The peristome is salient, thin, 
bearing one or two very small avicularia ; the peristomice is orbicular. The spira- 
men is placed on the median axis of the zooecium in the vicinity of the peristomice. 
side ; the dorsal is granular and bears 
two lateral rows of alternate salient 
avicularia with pivot. The zooecia 
are distinct , oval, a little elongated ; 
Measurements . — Peristomice 
\hpe= 0.05 mm. 
\lpe=0.05 mm. 
Zooecia 
I 7,2= 0.40 mm. 
! 4s =0.30 mm. 
Affinities . — Wo have only found the two specimens figured. They form a rather 
divergent type in this genus in the distinct form of the zooecia and in the nature 
of the walls. Some further study is necessary to properly classify this species. 
Occurrence. — Middle Jacksonian: Near Lenucls Ferry, South Carolina (rare). 
Cotypes. — Cat. No. 64168, U.S.N.M. 
Genus GIGANTOPORA Ridley, 1881. 
1881. Gigantopora Ridley, Zoological collections made during survey of H. M. S. Alert. 
Proceedings Zoological Society London, p. 47. 
The apertura bears a rimule. The frontal is an olocyst. The spiramen is 
inconstant ; it is almost as large as the apertura. 
