Discovery of a Pteraspidian Fish. 251 



Discovery of a Pteraspidian Fish in the 

 Silurian Rocks of New Brunswick. 



By G. F. Matthew. 



Although the existence of fish remains in the highest 

 heds of the Silurian system' in England and Bussia has 

 been known for many years, there has been until lately, a 

 singular dearth of evidence of the presence of these verte- 

 brates in beds of similar age in America. While the Devo- 

 nian system has been found to contain abundant remains of 

 fishes both in the Old World and the New, the Silurian sys- 

 tem in America, four years ago, was not known to have any 

 authentic remains of the hard parts of fisbes. 



Tbe fishes of the Silurian age are of two kinds 1 — Pteras- 

 pidian ganoids, known by the hard plates that covered the 

 anterior part of the body, and Selachians, whose presence 

 is known by the occurrence of spines of a peculiar kind. 

 The Pteraspidians had a peculiar, fine, but distinct striation 

 of the covering plates of the body, by which their remains 

 are easily recognized. These fossils have, within a few 

 years, been found in the Silurian rocks of Pennsylvania by 

 Prof. E. W. Claypole, to whose acumen and industry we 

 are indebted for many new facts respecting this interesting, 

 and as yet but imperfectly understood family of fishes. 



I propose herein to call attention to the discovery in 

 Canada, of fish remains of this peculiar type. The fossils 

 occur in beds of the Silurian system which are found on 

 the southern slope of the Nerepis Hills in King's County, 

 New Brunswick. These beds are of a very fine texture ; 

 they are evenly banded, silicious mud-rocks or hardened 

 shales, and pertain to No. 2 of the Mascareen Succession. 

 No. 3 of this series contains marine species such as mark 

 the Lower Helderberg Horizon of New York, or the 

 Ludlow of England. 



Only one example of the fish is known, and this exhibits 

 several plates belonging to its dermal covering. A part 

 of the rostrum and of the dorsal scute, and two lateral 



1 A representative of the tuberculated placoderms (Coccosteus) 

 occurs in Barrande's Etage F in Bohemia, but this family belongs 

 rather to Devonian than Silurian times. 



