832 General Notes, [ October, 
widths, from a few inches to a hundred and more feet, and they 
are nearly uninterrupted for a length of 4000 feet along the 
sloping surface of the hill. They are probably outflows from an 
ore body which is bedded with the limestone. Ata depth of 
thirty or forty feet, in some of the shafts, the veins change direc- 
tion so as to be conformable to the limestone, and many of the 
not recognizable by the eye. The green embolite is easily seen 
in specimens from all parts of this outcrop, and in some larger 
bodies of gangue it colors the entire rock—E&. D. Cope. 
A Fossit Tertiary CRAYFISH.—In a late number of this jour- 
nal, we described, under the name of Caméarus prima@vus, a fossil 
crayfish from the Lower Tertiary shales of Western Wyoming. 
The accompanying illustrations are kindly loaned by Professor 
F. V, Hayden; they appear in an account of this fossil published 
in the Bulletin of the U. S. Geological Survey of the Territories. 
The Cambarus primevus is exceedingly interesting from the fac 
that it represents a period in which heretofore no fossil cray fish 
has been found. The soft, fine, fissile, clayey shales of the Bear 
river tertiaries contain not only a good many herrin -like fish, 
but also genuine skates. The presence of land plants mingled 
with marine animals, shows that the waters were fresh, but com 
municated with the sea; the conditions were apparently those of 
a deep estuary into which fresh water streams ran, and in these 
rivers lived the crayfish. The deposits were probably lowet se 
cene, and may have been laid down nearer the ocean than those © 
Green river, if these divisions are to be retained for the Tertiary 
deposits of the West. At any rate, it is safe to say that the oct 
jarus primevus existed in the Bear river basin in early Tertaty 
times (the Green river epoch), while the Idaho Astac! were. 
much later age, possibly of the so-called Pliocene or transition 
period which connected the Tertiary with the Quaternary pene’ 
The Cambarus primevus may therefore be regarded as @ PF abe: 
ble Eocene crayfish. 
It thus appears that there is a tolerably complete set of forms 
of the modern type of crayfish, beginning with the Cr 
