Onrecorded Species of Fossils. OF 
pact to the naked eye, but exhibit under a microscope the 
typical and characteristic structure of the genus Solenopora 
(Dybowski). One of the specimens measures 5-40ths. of 
an inch in height and 15-40ths. of an inch in diameter, in 
the direction of the section which is cut partly at right 
angles to the tubes and partly in direction of the tubes 7. ¢, 
parallel to them. 
The species evidently belongs to the genus of which Sole- 
nopora compacta, Billings, is the type, and is almost identical 
with it. The tubes or zoccia, however, are more closely 
arranged and more numerous, being proportionally smaller 
in the Quebec specimens than in the typical examples 
from the lower beds of the Trenton formation of other 
portions of Canada. The tubes in the examples from Quebec 
also appear to be more tortuous, and at times resemble the 
structure observed in such forms as Girvanella or Strepho- 
chetus. Of the genus Solenopora, there appear to be two, and 
perhaps three distinct forms from the CambroSilurian or 
Ordovician strata of Canada. 
1. One of these, the typical Solenopora compacta, Billings, 
sp. (=Stromatopora compacta, Billings; —Stenopora com- 
pacta, Dawson ; =Tetradium Peachii, Nich. and Etheridge; 
=Solenopora spongioides, Dybowski; —Tetradium Peachii, 
var. Canadense, Foord ; (Cymatopora compacta, Dwight, 
-M.S.S.) occurs in abundance through a considerable thick- 
ness of the lower beds of the Trenton of Ontario and 
Quebec, and has zocecia varying from 1-320 th. to 1-400 th. 
ofan inch in diameter, whilst the Scotch representative 
described by Dr. Nicholson and Mr. Etheridge, jr., has 
zocecia which measure 1-420 th. of an inch—“ one-thirty- 
fifth of a line ”—in diameter. 
2. A second species of this genus Solenopora, occurs in the 
limestones of the Bird’s Hye and Black River formation at 
Paquette’s Rapids, on the Ottawa River. This locality is 
referred to by Billings as one of the places where this 
of the Cambro-Silurian rocks of Canada,” 1883. I very much prefer the terms 
“< autopores,” “ mesopores,’’ “‘ acanthopores,” etc., now employed by Messrs. Foord, 
Ulrich and other authors. 
