BRYOZOA. e205 
Nematopora.] 
short ridge joins the peristomes of each row of apertures, and longitudinally divides 
the concave spaces between the ends of the apertures. These spaces are larger in 
the subquadrate examples than in those having five rows of zocecia. They also have. 
the thin ridge that bounds each face more distinct from the elevated margins or 
peristomes of the zocecial apertures, which, in the pentagonal specimens, to a large 
extent also form the border of the faces. Longitudinal interspaces generally shorter 
than the length of the zocecial apertures ; about five of the latter in 2.5 mm.” 
Careful comparisons between the New York types of Nematoporu quadrata (loc. cit.) 
and the originals of N. ovalis have convinced me of their specific identity. My belief 
that the latter had larger zowcia proved incorrect, and as many of them have also 
the double ridges at the angles of the branches, which were regarded as the main 
peculiarity of the former, nothing is left to distinguish them. It is to be admitted, 
however, that none of the New York examples of the species so far seen have more 
than four rows of zocecia. 
The large size of its zocecial apertures will distinguish N. ovalis from the three 
species next described. N. lineata Billings, sp., of the Anticosti group, is a larger 
species with six or seven rows of zocecia. 
Formation and locality.—Galena shales, near Cannon Falls, Minnesota; Trenton limestone, Trenton 
Falls, New York, and Montreal,Canada. 
Mus. Reg. No. 8110. 
Nematopora GRANOoSA Ulyich. 
PLATE III, FIGS. 17-20. 
Nematopora granosa ULricu, 1890. Jour. Cin. Soc. Nat. Hist, vol. xii, p. 196. 
Original description: “Zoarium ramose; branches bifureating at rather long 
intervals, from 0.25 to 0,88 mm. in diameter, the smallest quadrangular in cross- 
section and with only four rows of zocecia; those of the average size, pentagonal, 
and with five rows of cells. Zocecial apertures small, narrow, about seven in each 
range in 2.5 mm., enclosed by a series of minute granules. Longitudinal interspaces 
with a small number of similar granules. Rows of apertures separated by more or 
less well-developed straight or slightly flexuous granulose ridges.” 
The papillose ornamentation of the ridges and interspaces, and the narrowness 
of the zocecial apertures of this species distinguish it from all the others having ther 
essential characters of Nematopora known to me. Under the microscope the general 
appearance of the zoarium is strikingly different from that of N. ovalis, with which 
it is associated. Equally marked differences will be noted when it is compared with 
N. delicatula and N. conferta, both of which likewise occur in the same beds. 
Externally, N. granosa presents not a little resemblance to small species of Rhombo- 
