OF DENISON UNIVERSITY. 
8l 
first brought to my notice several years ago by Rev. H. Herzer of 
Cleveland, O. Since then I have collected it myself at Richfield, O. 
Rev. Herzer’s were collected by him at localities in Cuyahoga Co. 
CYSTODIGTYA ZIGZAG, n.sp 
(Plate XIII, Fig. ii, iia.) 
Zoarium bifoliate, ramose, consisting of a main branch either 
nearly straight or more or less zigzag, from 1.3 mm. to 2.3 mm. wide, 
which throws off sub-alternately from the sides somewhat narrower 
branches. The latter may remain simple or become divided in a 
manner similar to the main branch. The lateral branches, if they 
may be so called, are given off at intervals of about 4 mm., so that 
about three occur on each side of a main branch in 20 mm. Zooecia 
in six to eight rows on the main branches and in six or seven on the 
lateral ones ; apertures widely separated, small, subelliptical, with a 
moderately developed peristome, highest on the outer or lunarial side ; 
as a rule they are not regularly arranged but sometimes curved diag- 
onal and longitudinal rows may be determined with distinctness. 
Usually about ten occur in 5 mm. longitudinally and between six and 
seven in 3 mm. diagonally. Interspaces rather wide ; in young or 
macerated specimens exhibiting sinuous striae ; in old examples either 
smooth or covered with exceedingly minute granules. 
This species is distinguished from others of the genus by the 
peculiar growth, it being the only one known to me branching in the 
manner above described. 
Formation and locality: — Cuyahoga shales of the Waverly series 
at Richfield O.; also in the Keokuk group at Keokuk, Iowa. 
CYSTODIGTYA SIMULANS. n. sp. 
(Plate XIII, Fig. 16.) 
Zoarium bifoliate, ramose, branching dichotomously at intervals 
of 8 mm. more or less. Branches acutely elliptical in cross section, 
from 2.8 mm. to 4.0 mm. wide, margined on each side with a narrow 
non-celluliferous strip. Zooecia apertures rather large, subcircular, 
with a strongly elevated and rather thick peristome when fully matur- 
ed. The apertures are often arranged in more or less curved trans- 
verse rows, which may extend completely across the width of a branch 
