302 G. J, HINDE ON CAMBRO-SILURIAN 
Conodonts were first noticed on the American continent by Dr. 
Newberry, who, in the second volume of the ‘ Palaeontology of Ohio’ 
(1875), figured several forms and discussed their probable relations, 
which he believed to be rather with fishes similar to Myxinoids 
than with invertebrates. All Dr. Newberry’s specimens were from 
the Lower Carboniferous at Bedford in the State of Ohio. 
The oldest strata in which I have met with Conodonts are thin 
layers of a dark limestone belonging to the Chazy formation of the 
Cambro-Silurian, which, if not the equivalents, are not far separate 
in relative age from the green sands and black shales of Russia, the 
lowest beds in which theso bodies haye been found there. ‘These 
Chazy beds are exposed on the banks of the Ottawa River at Gren- 
ville, in the province of Quebec, and are largely composed of the 
small tests of bivalve Crustaceans belonging to the genus Leperditia, 
associated with a few small Trilobites and Gasteropods. ‘There are 
no indications of any of the larger Crustacea or Mollusca to 
which these Conodonts could be referred; and they are altogether 
too large, even if they could be referred to either of these classes of 
animals, to have belonged to those whose tests are here preserved. 
Though the Conodonts are not unfrequent in these limestones, it is 
somewhat remarkable that they are all of one species, and this is 
one of the largest of the known compound forms. 
In the strata of the Cincinnati group exposed near Teronto, in 
which a few Conodonts appear, the rocks are principally micaceous 
flags and shales, and contain a great variety of fossils, Graptolites, 
Corals, Annelids, Brachiopods, Gasteropods, and Cephalopods of the 
genus Orthoceras, all well-known forms. No crustacean remains 
beyond scattered fragments of small Trilobites of the genus Caly- 
mene have been noticed. Whilst most of these fossils are in thin 
lenticular beds of limestone intervening between the flags and shales, 
the Conodonts are generally imbedded in the latter. In addition 
to a few compound teeth, there are also the simple spine-like forms 
of Conodonts; and it is worthy of notice that these simple forms are 
much more restricted in their distribution than the compound ; for 
whilst the latter appear from the Cambro-Silurian to the Lower 
Carboniferous, the simple teeth are only met with, both in America 
and in Russia, in the Cambro-Silurian. 
I have not as yet found any Conodonts in the Trenton and Utica 
sale rocks, which come betweeen the Chazy and the Cincinnati 
group, nor in any strata of the Silurian proper and the lower division 
of the Devonian; but mm the middle Devonian they reappear in 
great abundance. In strata of this age belonging to the upper 
beds of the Hamilton group of limestone and shales, exposed near 
the village of North Evans, on the south shore of Lake Hrie, New 
York State, they are very numerous; and one particular band of 
limestone, which I propose to designate the Conodont-bed, is filled 
with fragments of these small teeth. This limestone band varies 
from half an inch to three inches in thickness, and may be traced for 
some distance. On fracture it presents a dark subcrystalline aspect, 
with occasional particles of a green colour, and also crystals of iron- 
