APPENDIX.                                               645

the Cyclostomatous skeleton, but not more than it does with the like soft con¬
dition of Annelidous Worms and Naked Mollusks. But the teeth of aU known
Cyclostomes are less varied in form than are the Conodonts. Certain lingual
plates of Myxinoids are serrate, but not with a main denticle of much greater
length, such as shown in tbe form of Conodont caUed Machairodus by Pander.
Most Cyclostomous teeth are simple thick cones, with a subcircular base: and
every known tooth of a Cyclostomous Fish is much larger than any of the forms
of Conodont, which rarely equal half a line in length. This minuteness of size,
with the peculiarities of form, inclines me strongly to refer the Conodonts to
some soft Invertebrate genus. Certain parts of small Crustacea, e. g. the pygi¬
dium or tail of some minute Entomostraca, resemble in shape the more simple
Conodonts: but when we perceive that these bodies occur in thousands, de¬
tached, with entire bases, and that any part of the carapace or shell of an ento¬
mostracan or other crustacean has rarely been detected in the Conodont beds,
it is highly improbable that they can have belonged to an organism protected
by a substance as susceptible of preservation as their own substance. Much
more likely is it that the body to which the minute booklets were attached was
as soluble and perishable as the soft pulp upon which the Conodont was sheathed.
I find no form of spine, denticle, or booklet in any Echinoderm, and especially
in any soft-bodied one, to match the Conodonts, and conclude that they have
most analogy with the spines, or booklets, or denticles of Naked Mollusks and
Annelides.

^* The formal publication of these minute ambiguous bodies from the oldest
fossiliferous rocks as evidences of fishes is much to be deprecated."—Richard
Owen, British Museum, Nov. 18,1858.

M.—Silurian Fossils of Anticosti (p. 436).

The Silurian Fauna of Canada has recently been much enriched by the re¬
searches of the Colonial Smweyors and by admirable descriptions, by their
Palaeontologist, Mr. E. Billings, of the remains found in the great Island of
Anticosti at the mouth of the River St. Lawrence *.

The Zoophytes, MoUusks, and Crustaceans collected in the greater part of
the island, and amounting to 121 species, present an eminently Lower-Silurian
aspect; and whilst 85 of this number are new to geologists, 36 species are common
European and North-American types. Thus among the latter we find the
widely spread Brachiopods Leptaena sericea, Orthis testudinaria, and O. lynx,
as well as Bellerophon bilobatus, associated with Calymene Blumenbachii.

The fossUs in the overlying strata of the same island have been refen^ed by
Mr. Billings, after careful comparison and correlation, to the Llandovery rocks
of my classification, or what he terms Middle Silurian.

With the following just and philosophical remarks of this author I entirely
agree; for they are as true in reference to the Silurian rocks of North America
as they were proved to be in Bohemia by M. Barrande. Commenting upon the
difficulty (if not impossibility) of correlating all the Silurian divisions of Britain
with those of America, he thus writes:—" Erom what we know of the origin and
mode of accumulation of sedimentary strata, it is highly improbable that each
of the minor formations of one country should have its exact equivalent in
another land several thousands of miles away, although the larger gi-oups of
which these smaller ones are the component parts, may be well paralleled and

* Greological Surrey of Canada: ' Catalogue of the Silurian Fossils of the Island of Anticoqti' hv
E. BilHngs, 186fi.                                                                                                                         ' "^