40 F 
EKWAX RIVEH 
occurring at intervals of five inin. or more. Interstices much wider 
than the branches. Uissepiments aliout one inm. apart, or four and a 
half to five in the .space of five nun. Fene.sti ules longer than wide, 
irregular but somewhat rectangular, nearly or quite a mm. long and 
approximately about half .as wide us long. Zoa-cial aporlures circular, 
in two ranges, opening somewhat laterally, tw^enty in each range in 
the space of five mm., and three to four on each side in the length of 
a fenestrule, clo.sely disposed but separate, slightly irregular in their 
disposition, sometimes alternate on the two sides of the keel, sometimes 
opposite, their margins indenting the borders of the fenestrules. Under 
a highly magnifying simple lens, the keel appears to lie minutely 
.spinose In jihices. 
Ekwan river, portage road at falls : one fairly good specimeti. Mr. 
R. 8. Bassler, of the I". 8. National Museum, to whom the writer is 
indebted for critical suggestions in regard to tiie structural peculi- 
arities, and affinities of this and the following species, writes that the 
zofccial apertures of this Fenestello. “seem unusually large, but this is 
due to the removal of the outer investment of the zoarium.” 
PJuenopora Kceiratin<‘mis, sp. nov. 
Zoarium bifoliate, branching, consisting of a thin flattened frond 
which is six millimetres wide on an average, hut ten mm. wide at a 
bifurcation, and which bifurcates at intervals of about eleven mm. 
Zoiecia rliombic, a little longer tlian wide, seven in two millimetres 
measuring lengthwise and eight to eight and a half measuring trans- 
versely, divided tiy tliin, straight longitudinal partitions, which form 
their sides and separate them into longitudinal rows. Apertures of 
the zofccia obliquely oval. Surface marked by arching .siriie, which 
curve convexly forward. 
Small island in the northern Sutton Mill lake, one specimen. In 
regard to this specimen, IM. Bassler writes as follows : It is “ a 77^(7;- 
nopora closely allied to several Clinton spocic.s, but which I should 
regard as new. In zon'cial .‘structure is is very close to P, multi ficln^ 
Hall, and especially to P. limhrinta, dame.s, /'. mu/tijl'la has a ditler- 
rent zoo'cial growth and .slightly larger zotecia. J\ /nnhnaf<i has about 
the same zoiecial measurements, but the growth of the zoarium is quite 
different.’' 
Seven other species of Phomopora are known to occur in the Cambro- 
Silurian and Silurian rocks of Canada. The.se are ; /'. in:ipiens, 
Ulrich, from the Trenton limestone of Montreal; P. comtellata, P. 
ensiformis and /’. explanata, Hall, also P. punctata, Nicholson and 
