4 The American Geologist. -iniy, 1892 
withsttinding the uncertainty resulting from our inability at pres- 
ent to pronounce on its exact position. The blunt tubercle on its 
lower side shows all the usual marks of having been a denticular 
process, and it almost certainl}- lay close behind the great tooth 
last described. In default of certainty on this point, however. I 
prefer merely to indicate its probabilities, and to leave its deter- 
mination for the future. 
Found in the Cleveland shale, near Berea, ()., by Dr. W. Clark, and 
named for him iu acknowledgement of his patience and perseverance in 
exhuming and extricating it.* 
THESTRATIGRAPHIC POSITION OF THE OGISHKE 
CONGLOMERATE OF NORTHEASTERN 
MINNESOTA.t 
By Uly S. Grant, Minneapolis. 
In the region of Ogishke Muncie or Kingfisher lake (T. 65-G, Lake 
Co. , Minnesota) is a marked conglomerate of considerable extent. 
It is well known to lake Superior geologists as the Ogishke con- 
glomerate. It consists of pebbles of slates, graywackes and 
other clastic rocks, together with those of acid and basic erup- 
tives, all embedded in a matrix of varying composition. Fre- 
(^uently this matrix is a dark or light colored argillaceous slate ; 
at other times it resembles graywacke, and again it acquires a 
greenish color and approaches the chloritic schist of this region. 
But perhaps the most characteristic facies of the matrix is an 
impure quartzyte with angular and rounded grains of quartz; 
fragments of feldspar and hornblende are also present. The 
pebbles are of all sizes up to those over a foot in diameter. They 
are usually well rounded and are sometimes elongated in the 
direction of the strike. The rock has been more or less meta- 
morphosed and in places the pebbles approach so near the matrix 
in character that the conglomeritic nature of the rock can be seen 
only on favorable weathered surfaces. The beds as a rule stand 
nearly vertical with a general northeasterly strike. However, 
it is often the case that no lamination can be discerned. The 
conglomerate, as far as known, fades otf both along and across 
the strike, by simple loss of the pebbles, into the argillytes, green- 
*A short notice of this fossil was given at the meeting of the Geological 
Society of America at Columbus, O., in December, 1891, and the name 
was then lirst proposed. 
tPublished with the permission of the State Geologist of Minnesota. 
Read before the Minnesota Academy of Natural Sciences, June 14, 1892. 
