NORTH AMERICAN EARLY TERTIARY BRYOZOA. 
243 
De Gregorio in his Monograph on the Eocene of Alabama has created for the 
group containing L. radiata Lamarck, 1816, L. fenestrata De Gregorio, 1890, and 
L. punctata Leymerie, 1845, a special genus Dimiclausa , in which L. ovata and 
L. verrucosa could be introduced. The essential character is the presence of hydro- 
static cellules (cellulis medianis clausia). It is undeniable that the group of species 
just cited forms a rather homogenous assemblage characterized chiefly by the great 
development of the calcareous crvptocyst. But, though the hydrostatic cellules 
may be constant, they are not peculiar to it, for not only do they exist on many 
other species of Lunularia , but they have the same constancy in the genus Trocho- 
pora, , where the mode of growth is totally different. These species of Lunularia 
are perhaps identical or closely related forms, but they do not have different func- 
tions from other species, so that they can not be. separated generically. 
In the interior (fig. 9) the zooecia exhibit a convexity, often supporting the 
ovicell. This convexity is characteristic of the genus. 
The larva always attached itself to a large grain of sand, which fact explains 
the large number of hydrostatic zooecia permitting the zoarium to lighten itself 
and thus escape the dangerous zone of the sand. 
In the transverse sections the very thick zoarium is formed of many celled 
segments radiating from the center or from a bifurcation. 
Occurrence. — Middle Jacksonian: Wilmington, North Carolina (common); 
Rich Hill, Crawford County, Georgia; 18 miles west of Wrightsville, Johnson 
County, Georgia (rare) ; 12 miles southeast of Marshallville, Georgia (rare) ; Bal- 
dock, Barnwell County, South Carolina (rare) ; 3£ miles south of Perry, Georgia 
(rare). 
Upper Jacksonian (Ocala limestone) : Chipola River, east of Marianna. 
Florida (rare); Bainbridge, Georgia (rare). 
Vicksburgian (“ Chimney rock ” of Marianna limestone) : One mile north of 
Monroeville, Alabama. 
Cotypes.- — Cat. Nos. 63992, 63993, U.S.N.M. 
LUNULARIA LIGULATA, new species. 
Plate 13, figs. 10-12. 
Description. — The zoarium is a concave Lunulites, much expanded. The zooecia 
are rectangular, transverse, distinct; the mural rim is thick and distinct from the 
cryptocyst, which is deep, smaller than the opesium, and very finely granulated. 
The opesium, orbicular or elliptical, is surrounded by a prominent collar. The ovicell 
is a large distal convexity. The hydrostatic zooecia have a false opesium partially 
obstructed by a wide calcareous tongue. The vibracula are elongated, narrow 
fusiform, deeply embedded, disposed in distinct rows. The inner side has flat or 
slightly convex radial ribs, perforated with small, scattered pores. 
Lz— 0.20 mm. 
lz— 0.30 mm. 
Measurements- 
. fAo=0.16mm. 
-°P esm Uo=0.Umm. 
\Lv— 0.20 mm. 
LZ-y =0.10 mm. 
Nbracula j 
