NORTH AMERICAN EARLY TERTIARY BRYOZOA. 
727 
Florida (common) ; Old Factory, about 14 miles above Bainbridge, Georgia (very 
rare). 
Vicksburgian (Marianna limestone) : Salt Mountain, 5 miles south of Jackson, 
Alabama (common) ; West bank Conecuh River, Escambia County, Alabama (very 
rare) ; One mile north of Monroeville, Alabama (very common) ; Murder Creek, 
east of Castlebury, Conecuh County, Alabama (very common). 
Geological distribution. — Cretaceous-Recent. Cosmopolitan in Europe and 
America. 
Habitat . — Cosmopolitan in both hemispheres and in the warm and temperate 
zones. This is a species of the depths; it appears first at 40 meters; attains its 
maximum of abundance toward 100 meters, and may descend almost to 330 meters. 
It affords, therefore, a very useful measure of depth. 
Plesiotypes. — Cat. Nos. 65437, 65438, U.S.N.M. 
MECYNOECIA LUVERNENSIS, new species. 
Plate 109, figs. 10-12. 
Description . — The zoarium is au unbranched Filisparsa in which the noncellu- 
liferous dorsal face is transversally wrinkled. The tubes are short, little visible, 
elevated at their extremity and terminated by a very short peristomie elevated 
almost vertically; the peristome is thick, orbicular. The ovicell is large, salient, 
globular; the oeciostome is elliptical, salient, transverse, supported on another 
tube. 
[ Diameter of the peristome 0.20-0.22 mm. 
Measurements . — Diameter of the apertura 0.16 mm. 
[ Diameter between the peristomes 0.25 mm. 
Occurrence . — Miclwayan (Clayton limestone) : Luverne, Crenshaw County, 
Alabama (rare). 
Cotypes. — Cat. No. 65257, U.S.N.M. 
MECYNOECIA CYLINDRICA, new species. 
Plate 127, figs. 1-7. 
Description . — The zoarium is an Entalophora , regularly cylindrical , bifurcated. 
The tubes are cylindrical, visible, separated by a very thin, salient thread; the 
peristomes are salient, orbicular, regularly arranged in quincunx. The ovicell is 
a large pyriform sack whose oeciostome is isolated. 
Diameter of the peristome 0.10-0.12 nun. 
Distance between the peristomes 0.42-0.46 mm. 
Separation of the peristomes 0.36 mm. 
Diameter of the branches 1.00 mm. 
Affinities . — This species is very well characterized by its pyriform ovicell, its 
cylindrical and regular branches, and by its zooecial margins. It is much smaller 
M easurements . — 
