Editorial Comment. 329 
EDITORIAL COMMENT. 
The oldest fish remains known. — The most important 
announcement of palaeontological discovery during the past 
season is that recently made by Mr. C. D. Walcott of the 
U. S. Geological Survey of the occurrence of fish-remains 
in the Lower Silurian rocks of Colorado. The Silurians of 
Herefordshire and Shropshire in England have long been known 
to contain abundant relics of the early vertebrates, but these re- 
mained for mairy years the only recognized traces of this sub- 
kingdom below the Devonian strata, for though similar discoveries 
were reported from Bohemia and the Hartz, yet as the accompani- 
ments of these indicated Devonian rather than Silurian date they 
have been regarded as of later age, especially as the fossils be- 
longed to genera considered in England to characterize the 
Devonian rather than the Silurian strata. (Asterolepis, Coccosteus 
and Ctenacanthus. ) 
The island of (Esel in the Baltic sea is thus far the only 
European station outside of the British Isles which has yielded 
indications of a Silurian fish-fauna. These were of an affinit}' and 
in associations which confirmed the inferences from the English 
specimens as to the nature of the earliest vertebrate life. They 
were in both cases of the same type and consisted of simple shields 
of one or more pieces covering the dorsal and perhaps also the 
ventral surfaces of the animal. The fossils belong to the genera, 
Cyathaspis and Scajyhasjjis, if indeed these were not parts of the 
same species. 
In 1885 similar remains were found by Dr. E. W. Cla} r pole in 
the Onondaga rocks of Perry Co. , Pa. , on a horizon a little lower 
than the Lower Ludlow of England from which the oldest speci- 
mens there found had been obtained. These form the genus 
Palceaspis. He also announced a spine (Onchus jwinsylvaniciis) 
from the Clinton beds indicating the existence of elasmobranch 
fish at a }-et earlier date. 
In 1888 Mr. Matthew discovered in strata referred to the Lower 
Helderberg in New Brunswick remains of a similar nature indicat- 
ing the existence of fish in the seas of that region in Silurian 
time. His species is Diplaspis acadica. 
The last find which has called out this note was made as said 
above by Mr. Walcott in a collection of fossils found near Cafion 
