68 
BULLETIN OF THE LABORATORIES 
erage width not 0.38 mm.; bifurcation frequent, the intervals varying 
between i mm. and 4 mm, Carina thin, moderately elevated, faint- 
ly nodose, the nodes distant from each other about o. 5 mm. Zooecia 
in two ranges, eighteen in each in 5 mm.; apertures circular, o. ii 
mm. in diameter, directed a little obliquely upward and outward, with 
well developed peristome drawn out posteriorly into an oblique ridge, 
and projecting laterally so as to indent the border of the fenestrule. 
Dissephnents depressed, thin, finely striated, expanding very little at 
their junction with the branches. Fenestrules irregular in shape and 
size, with from seven to nine in 10 mm. 
On the reverse the branches and dissepiments strongly rounded, 
and covered with short striations, or minute granules. The fenestrules 
here are wider than on the other side of the zoarium. 
This neat species is related to F. albida var. richfieldensis and F. 
jilistriata, Ulrich,* from the Burlington limestone of Iowa. From 
the former it differs in the smaller zoarium, more flexuous branches, 
narrower and smaller fenestrules, and more closely arranged zooecia 
apertures. The reverse side of the branches is also differently marked. 
These differences also apply when compared with the Burlington spe- 
cies, that form being further distinguished by its finely striated ob- 
verse. 
Formation and locality : — Cuyahoga Valley below second fall. 
FENESTELLA SUBFLEXUOSA, n. sp. 
(Plate XIII, Fig. 6.) 
Zoarium a small leaf-shaped expansion, 20 mm. long and 16 or 18 
mm. wide. 
Obverse: — Branches slender, laterally compressed, between 0.3 
mm. and 0.4 mm- wide, diverging rapidly, irregularly fiexuous, seven 
or eight in 5 mm.; bifurcations frequent, so far as observed, the in- 
tervals vary between 1.5 mm. and 6 mm. Carina thin, strongly ele- 
vated, carrying small but rather prominent nodes 0.2 to 0.3 mm. 
apart. Zooecia in two ranges, seventeen or eighteen in 5 mm.; aper- 
tures circular, small, about 0.08 mm. in diameter, nearly direct, sur- 
rounded by well developed peristome, a little more than their diame- 
ter apart. Dissepiments very thin, sharply angular, only a little de- 
pressed, not expanding at their junction with the branches. Fenes- 
trules of irregular form and unequal sizes, unusually eight in 10 mm. 
