CORALS AND BRYOZOA. 
113 
b. Forms having a smooth carina. 
Fenestella biseriata, n. sp. 
PLATE XLII, FIGS. 16-18. 
Bryozoum infundibuliform. Branches moderately slender, width above a bifur¬ 
cation .35 mm., increasing to .50 mm.; very gradually enlarging, straight, 
somewhat rigid in appearance, rounded or sub-angular, finely striated, occa¬ 
sionally with minute nodes ; bifurcations distant. Interstices wider than the 
branches, sometimes twice the width. Dissepiments very slender, width .22 
mm., rounded or sub-angular, sometimes slightly carinated, nearly on a plane 
with the branches, five in the space of 5.50 mm. Fenestrules sub-quad¬ 
rangular or oval, length nearly .80 mm., width usually about .50 mm. 
On the celluliferous face the branches are angular. Dissepiments rounded 
or sub-angular, very much depressed. Fenestrules a little narrower than on 
the opposite face. Cell apertures in two ranges, opening somewhat laterally, 
twenty in the space of 5 mm., separated by the diameter of an aperture: 
margins thin, slightly elevated. Surface between ranges of apertures angular, 
sub-carinated. 
Formation and locality. 
county, N. Y. 
Upper Helderberg group, Cherry Valley, Otsego 
Fenestella peculiaris. 
PLATE XLII, FIGS. 19-21. 
Fenestella ■peculiaris, Hai.l. Report of State Geologist for 1882. Expl. pi. 33, figs. 19-21. 1883. 
Bryozoum infundibuliform. Branches slender, very gradually enlarging; width 
above a bifurcation .33 mm., increasing to .40 or .45 mm.; obtusely angular, 
except for a short distance before bifurcating, carinated, carina and other 
parts of the branch nodose or granulose. When the frond is much macerated 
the nodes are obsolete and the carina is much more prominent than in well- 
preserved specimens. Interstices a little wider than the branches. Dissepi¬ 
ments slender, width .30 mm., flattened, granulose, slightly depressed, five 
in the space of 5 mm. Fenestrules oval, length .70 mm., width .35 to 
.40 mm. 
