1896.] Geology and Paleontotogy. 819 
“The discovery of the Olenellus or Lower Cambrian fauna in the 
Reading sandstone practically completes the correlation of the South 
Mountain, Chickies and Reading quartzites, and establishes the cor- 
rectness of the early correlations of McClure, Eaton, Emmons and 
Rogers. They all considered the basal quartzite as the same formation 
from Vermont to Tennessee; and the discoveries of recent years have 
proved that the basal sandstones of Alabama, Tennessee and Virginia 
(Chilhowee quartzite); Maryland, Pennsylvania and New Jersey 
(Reading quartzite) ; New York and Vermont (Bennington quartzite), 
were all deposited in Lower Cambrian time, and that they contain the 
characteristic Olenellus fauna throughout their geographic distribution. 
The superjacent limestones carry the Olenellus fauna in their lower 
portions in northern and southern Vermont, eastern New York, New 
Jersey and Pennsylvania. To the south of Pennsylvania the lower 
portions of the limestones appear to be represented by shales, and the 
Upper and Middle Cambrian faunas are found in the lower half of the 
Knox dolomite series of Tennessee, and they will probably be discov- 
ered in the same series in Virginia and Maryland when a thorough 
search is made for them. The same may be predicted, but with less 
assurance, for the northern belt of limestone crossing Pennsylvania into 
New Jersey as the limestones between the Olenellus zone and the 
Trenton zone represent the intervals of the Middle and Upper Cam- 
brian and the Lower Ordovician, or the Calciferous and Chazy zones of 
the New York section.” 
Nothing was discovered upon which could be based a line of demarca- 
tion between the Cambrian and Ordovician linestones in the series 
under discussion. The division is still an open question to be decided 
by future revelations of lithologicand paleontologic characters. (Bull. 
U. S. Geol. Surv., No. 134, Washington, 1896.) 
Structure of Uintacrinus.—Since Uintacrinus was first made 
known by Grinnell, some twenty years ago, little notice has been taken 
of the form. Of late, however, special interest in the type has been 
revived, and the form comes in for consideration in several important 
articles. Among them are W. B. Clark’s review of the Mesozoic 
Echinodermata of the United States’, in which all known material is 
described, and the structure amply illustrated by figures. Shortly 
after Williston and Hill’ gave some “ Notes on Uintacrinus socialis ” 
as found in Kansas. Still more recently Bather’ has gone over all the 
1U. S. Geol. Sur., Bull. 97, pp. 21-24, 1893. 
2? Kansas Univ. Quarterly, Vol. ITI, pp. 19-21, 1894. 
* Proc. Zool. Soc., London, 1895, pp. 974-1004, 1896. 
