344 The American Geologist. December, 1902. 
The species is nearest related to F. sevillensis Ulrich, from which 
it is not readily distinguished if the reverse face is viewed, except 
with worn specimens when the smaller zooecia show. The zooecia are 
larger than those of F. parvipora n. sp. The distinguishing features 
are the large spines on a carina. The obverse face is not very apt to 
be confused with other species. F. limbata Foerste has more promin- 
ent apertures and smaller proportions. Type specimens in the museum 
of the University of Nebraska, Lincoln, Nebraska. 
Position and locality: Coal Measures; Roca and Dawson, Ne- 
braska. This is a common fossil in the Warner quarry one mile east 
of Roca. 
Fenestella parvipora n. sp. 
PI. XXr. Figs. 6. 7. 
Zoarium an expanding foliar net work of medium size. Branches 
on the reverse, straight to sinuous, convex, finely striated if worn, 
more than their own diameter apart, average diameter 0.24 mm., nine 
or ten in 5 mm. ; bifurcations at distances of 2 to 4 mm. Obverse 
face subcarinate ; the carina is represented by a line on which occur 
very small nodes; nodes scarcely discernible, 0.04 mm- at bases, 0.15 
to 0.21 mm. apart. 
Dissepiments straight, long, cylindrical, about one-third as wide as 
the branches, not much depressed on the reverse face ; depressed on 
the obverse. Fenestrules oblong, quite large for the size of the branch- 
es, average 0.5 to 0.55 mm. long, 0.31 mm. wide ; the narrowest are 
0.28 mm. ; seven and one-half in 5 mm. 
Zooecia small, in two alternating ranges, three or four to each fen- 
estrule. Apertures very small, circular, pustuliform with rounded 
subconial peristomes, 0.09 mm. across including the peristome, face 
obliquely outward, more than their own diameter apart, 25 in 5 mm. 
This species resembles F, sevellensis Ulrich in having a similar re- 
verse face, but is distinct on account of the number, size and disposi- 
tion of zooecia. It is not apt to be confused with another member of 
the genus. F. gracilis n. sp. l\as a definite carina with larger spines, 
larger apertures and very different fenestrules. The writer knows of 
no species of the genus with as small zooecia and zooecial apertures. 
Type in the museum of the University of Nebraska, Lincoln. Ne- 
braska. 
Position and locality: Coal Measures; Roca, Nebraska. 
Fenestella gracilis n. sp. 
PI. XXr. Figs. S, 9. 
Zoarium a regular foliar expansion of large size as indicated by 
numerous incomplete specimens. Branches on the reverse, about equal 
in size, straight or slightly flexuous, spread little when bifurcating, 
appear cylindrical, with longitudinal striae; average width 0.25 mm., 
nine to twelve in 5 mm. The obverse face has a straight carina, 0.07 
mm. wide, with rounded summit, bearing a row of sharp, conical 
