242 
BULLETIN OF THE NATURAL HISTORY SOCIETY. 
Charlotte county, ajnd in the past summer collections of the 
plant remains were made, and are now undergoing examination 
and study. We propose to give here a brief notice of the mode 
of occurrence of these plants, and to state in a general way, what 
they appear to teach. 
The plants occur in beds along a shore line on the eastern 
side of Beaver Harbor. On the western side of the harbor 
south of the village there is an exposure of the characteristic 
black silicious slates of No. 2 of the Mascareen phase of the 
Silurian series ; above these are sandstones which further west 
carry a Niagara fauna ; hence, (and for other reasons) these black 
slates are regarded as of Clinton age. The black silicious slates do 
not appear on the eastern side of Beaver Harbor, but their place 
would be to the south of and above the plant beds and associated 
strata on that side of the harbour. The composition of the 
measures here, and the fact that the base of the Silurian system 
is seen on this shore, leads us to regard these plant beds as of 
Medina age. 
A section of these rocks is presented herewith, and the con- 
tact of the Silurian with an older unconformable series of 
sediments is shown. The older set of beds show a core of 
massive gray quartzites, in a ridge, covered on each side by 
masses of red volcanic ash rocks (grits and felsites), fragments 
of both members of this series being plentiful as boulders and 
pebbles in the overlying Silurian conglomerates. The section 
shows a blank in the middle where there is a gravelly beach, which 
probably is underlain in part by dark gray shales, such rocks being 
found at this horizon, on the north end of the village beach at 
Beaver Harbor, and in the keyhole pond at this north end of the 
harbor. Thus it will be seen that the plant beds, from which the 
fossils were taken, are not at the bottom of the Medina division 
(No. 1 of the Mascareen section), but towards its top. 
The plants of this flora do not show much variety of species, 
but the uniformity in this respect enables one to speak with 
greater confidence of the characteristics of the species that do 
occur. One plant, of a new genus allied to Psilophytoin, is 
