Meeting of the American Association. — Uphani. 223 
covered some time previously by Mr. F. K. Mixer. All the elements 
were retained in their natural position, so that there can be no longer 
any doubt as to the reconstruction of the under surface of this genus. 
The specimen recalls the somewhat similar one of Holonema exhibited 
by Prof. H. S. Williams at the Indianapolis meeting of the Association 
in 1890, these two being the only instances known where the ventral 
plates of the respective genera are preserved in situ. 
12. TIlc Discovery of a new Fish Fauna, from the Devonian rocks of 
Southwestern New York. F. K. Mixer. The oldest remains of fishes 
from this region were discovered in the Corniferous limestone, and were 
noticed in the Bulletin of the Buffalo Society of Natural Sciences (vol. 
V, p. 8i, 1888). These remains consist of the spines and teeth of sela- 
chians, similar to those described by Dr. Newberry from the Devonian 
of Ohio. 
When we come upward to the rocks of Hamilton age, we find that 
nothing in the class of fishes has been heretofore described, so far as 
known to the writer, from this region. The remains now discovered in 
this formation consist of determinable plates of dinichthyid fishes. 
The next horizon, in ascending geological sequence, to reveal fish re- 
mains is that of the Black shales in the Portage series. From these 
shales a plate of a small Dinichthys, and two ganoid fishes, have been 
described. More recently the mandibles of a dinichthyid, besides more 
perfect remains of these ganoids, have been discovered in these shales. 
13. Interylacial clianye of course, with gorge erosion, of the St. Croix 
river', in Minnesota and Wisconsin. Wakken Upham. (Read by Prof. 
C. W. Hall.) An outline of a lecture at Taylor's Falls, Minn., substan- 
tially the same as this paper, was given in the American Geologist for 
last April (p. 260). The Aftonian interglacial epoch in southern Minne- 
sota, as indicated by the erosion of the St. Croix Dalles, was probably 
longer than the Postglacial period. From the corresponding intergla- 
cial valley of the Mississippi river west of Minneapolis, filled with drift 
but marked by a series of lakes. Prof. N. H. Winchell. in the Am. Geol- 
ogist (vol. x, pp. 69-80, with map and sections, and p. 302, Aug. and 
Nov., 1892), estimates the time required for its erosion (since named by 
Chamberlin the Aftonian epoch) as about 15,000 years, which seems 
well accordant with the interglacial erosion of the St. Croix valley. 
14. The Preglacial CuyaJtoga Gorge in (Jlereland, Ohio. Warren 
Upham. (Read by Prof. G. F. Wright.) This paper is based on in- 
formation supplied by Mr. S. J. Pierce of Cleveland, derived chiefiy from 
deep well borings which have V>een made during several years past un- 
der the direction of Mr. F. S. Gilbert, contractor, also of Cleveland, 
showing that the preglacial Cuyahoga valley in its last eight miles, 
passing through Newburg and Cleveland, has a depth of 350 to 470 feet 
below the surface of lake Erie. The deepest previously published well 
section in drift at Cleveland was that of the Standard Oil Company, 
recorded in the reports of the Geological Survey of Ohio by Newl)erry, 
which, situated near the mouth of Kingsbury run, reached the bed 
rock of shale 228 feet below the levi'i of the river and lake. Even that 
