J. F. Whiteaves—New Species of Ptericthys. - 188 
Homostius Asmuss, and in part with Heterostius. On the other 
hand, Prof. R. Owen claims* that Piericthys should be retained 
in preference to Asterolepis and Bothriolepis Hichwald, on the 
ground that “‘no recognizable generic characters were associa- 
ted” with the latter names; and, as this view has been very 
generally accepted by paleontologists, it will be adopted pro- 
visionally in these notes. 
e only remains of fossil fishes yet recorded as occurring 
in the Paleozoic rocks of North America which may prove to 
be referable to the genus Ptericthys, are some isolated scales 
from the Catskill group of Tioga County, Pennsylvania, de- 
scribed by Prof. Hall in 1848 as Sauripteris Taylort, but which 
Dr. Newberry thinks have the characteristic sculpture of Both- 
riolepis. The name Ptericthys Norwoodensis, although inadver- 
tently cited by Mr. 8S. A. Miller, on page 288 of his ‘Ameri- 
can Paleozoic Fossils,” should have been rejected long ago, 
for in the first volume of the Second Series of this Journal, 
dated 1846, Drs. Norwood and Owen showed that the specimen 
or which it was suggested is the type of their genus Macropeta- 
ss and of a species which they described as J. rapheido- 
abis 
In the summer of 1879, Mr. R. W. Ells, M.A., of the Geo- 
logical Survey of Canada, had the good fortune to find, in a 
concretionary nodule of argillite from the north side of the 
Baie des Chaleurs immediately opposite Dalhousie, a mould of 
the plastron or ventral surface of a true Plericthys (as defined 
by Prof. Owen) with one of the pectoral spines in situ. At 
the earliest practicable opportunity, Mr. Ells revisited the 
locality, and in the first week of June last obtained three ex- 
quisitely preserved specimens of the buckler of the same spe- 
cles and several fragments; also some isolated scales of a 
Glyptolepis. The finest example of the Canadian Ptericthys 
collected by Mr. Ells had a large piece broken off the left mar- 
n when it was found, but with this exception the whole of 
the upper surface of the helmet and buckler is finely exposed 
(the plastron being partly covered by the matrix), and the out- 
ine of the orbital opening is clearly defined. A few weeks 
later, Mr. T. C. Weston, also of the Canadian Survey, collected 
an additional number of fine specimens of the Plericthys from 
this locality, some of which illustrate admirably the shape, 
sculpture and mode of articulation of the pectoral spines. 
Associated with these there are, in Mr. Weston’s collection, a 
nearly perfect but badly distorted specimen of a @lyptolepis 
fully seven inches in length, some fragments of Psilophyton, 
and a spore case of a idodendron. 
Taken collectively, the specimens thus far obtained of the 
* Paleontology, Second Edition, page 141, 
