NORTH AMERICAN EARLY TERTIARY BRYOZOA. 
319 
Affinities. — The aspect of this species is that of a worn zoarium, thus recalling 
Heteropora. The examination of the transverse section indicates clearly a Cheilos- 
tome despite this deceptive appearance. The ascopore is not regularly placed and 
it is often little discernible as in Acropora mamillata D’Archiac, 1846; it differs 
from the latter species in the absence of a salient peristome. 
Fig. 90. — Genus Acropora Reuss, 1869. 
A-E. Acropora gracilis Milne-Edwards, 1836. A. Zooecia. (After Milne-Edwards, 1836.) 
B. Zooecia and avicularia. (After Hincks, 1881.) C. Zoaria, natural size. D. Operculum, X 
140. E. Longitudinal section. (C-E after Levinsen, 1909.) 
F-K. Acropora coronata Reuss, 1869. F, G, H. Three views of zooecia, showing variations 
of the avicularia, X 95. I. Termination of a branch, natural size, and X 12 showing openings 
for articular tubes. J. Small form (cf, Acropora labrosa Reuss). K. Diagrammatic section 
through a zooecium ; asc, ascopore; op, operculum; tb, tubules. (F-K after Waters, 1891.) 
Occurrence . — Midway an (Clayton limestone) : One mile west of Fort Gaines, 
Georgia (rare). 
Cotypes. — Cat. No. 63817, U.S.N.M. 
ACROPORA SAILLANS, new species. 
Plate 85, figs. 4-12. 
Description .— The zoarium is free, cylindrical, bifurcated, formed of 5 or 6 
longitudinal rows of zooecia. The zooecia are distinct, large, elliptical; the frontal 
