Nezv Bryozoa from Nebraska. — Condra. 351 
finer growth, a less binodate appearance and a larger number of aper- 
tures. The principal characters of this species are found in the double 
row of alternating nodes on a broad carina and in the robust appear- 
ance. Type specimens in the museum of the University of Nebraska, 
Lincoln, Nebraska. 
Position and locality: Coal Measures; South Bend, Weeping 
Water, and Roca, Nebraska. 
Polypora bassleri n. sp. 
PI. XXII. Figs. 8, 9; PI. XXIII, Fig. X. 
Zoarium and expanding growth of medium size ; branches not very 
straight, narrowly or evenly rounded on the reverse resembling, when 
narrow, P. submarginata Meek ; evenly rounded on the reverse, with 
small or large spines distributed among the apertures about as in P. 
spinulifera Ulrich ; spines located on thin zigzag ridges between the 
ranges or on a fairly even surface; about five branches occur in 5 mm., 
each having an average diameter of 0.7 mm., 0.8 to 0.9 mm. just below 
a bifurcation. 
Dissepiments on the obverse, one-half as wide to as wide as long, 
about 0.35 mm. wide, broadly rounded, expanded terminally. F'enes- 
trules elliptical to oblong, average 0.9 to i.o mm. long by 0.4 wide on 
the obverse, with four in 5 mm., larger on the reverse face. 
Zooecia in three to six, usually closely placed alternating ranges, 
commonly four above a bifurcation ; five, rarely four, sometimes six, 
in each range to the fenestrule. Apertures circular, o-ii mm. across, 
one and one-half diameters apart, nineteen or twenty in 5 mm. with 
peristomes around the apertures of the lateral ranges ; zooecia of the 
other ranges with peristomes or open into small depressions between 
the zigzag lines which may separate the ranges ; apertures usually less 
than their own diameter apart from those in the adjacent or alternat- 
ing ranges. This species resembles P. approximata Ulrich, but is 
structurally different. The growth in one form is more diffuse the 
reverse face of which resembles smaller P. submarginata Meek. In 
fact some of the specimens commonly referred to that species belong 
here. The other form of growth is nearer P. approximata and P. 
spinulifera. The ranges of zooecia are more crowded in old than in 
young growth. Little area or space is left between the alternating 
ranges. P. approximata Ulrich is more robust and differs structurally. 
The name is given in honor of Mr. R. S. Bassler who has rendered 
the writer valuable assistance. Type specimens in the museum of the 
University of Nebraska, Lincoln, Nebraska. 
Position and locality: Coal Measures; Louisville, Weeping Water, 
Nebraska. 
Polypora reversipora n. sp. 
PI. XXIII, Fig. 2-5. 
Zoarium a flat foliar expansion of large size. Branches on the re- 
verse, stout, flexuous, bending into and away from the dissepiments, 
