42 The American Geologist. January, \mi 
Several papers, of a character rather sensational, were pub- 
lished here and also in Europe, by the paheontologist of the 
U. S. Geological Survey, and the result as stated, in the book : 
(J or relation papers — CV<w6/v'fn/, "Bull. U. S. Geol. Survey," No. 
81, p. 360, Washington, 1891-92, is the placing of the Georgia 
formation in the Lower Taconic (called by some Lower Cam- 
brian), below the Paradoxides zone of St. John (New Bruns- 
wick), of eastern Newfoundland, and of Braintree (Massachu- 
setts), which then is regarded as Middle Taconic (Middle 
Cambrian). 
Several years have passed since the publication of the view 
and opinion, expressed with some emphasis and remarkable 
assurance, in the volume Correlation! papers — Cambrian.: and 
nothing has been found to sustain that classification; on the 
contrary, the best experts for trilobites in America consider 
the JSIliptocejfhalvs (OleneUns) thompsoni of Georgia as 
generically different from the Olenellus hrdgc/eri of Manuel's 
brook. The latter probably is congeneric with Olenellus kjer- 
nlji, of Scandinavia, and both species — O. hroggeri and O. 
kjeridfi — belong to the genua Holmia, entirely different from 
the genus UlliptocepJiahis (Olenellus) of Georgia, So we have 
an example of confusion in the classification and correlation 
of strata brought up by an erroneous determination of a ge- 
neric group of trilobites.* 
What a strange destiny for the Georgia trilobite; first, it 
was determined as an Oleiius instead of an Elliptocephalus 
and placed stratigraphically on the top and consequently 
above the second fauna, instead of belonging to the primor- 
dial fauna; second, it was taken from the Olenus and called 
Barrandia. then afterward Olenellvs and considered as a 
Potsdam fossil, that is to say, placed at the summit of the 
Upper Cambrian. Finally it was placed at the bottom of the 
Lower Cambrian, running a race through 25,000 feet of strata 
and two great geological epochs of the earth. And now it is 
restored to its exact place, in the upper part of the Middle 
Taconic (Middle Cambrian). 
*The present writer pointed out the mistake in referring the New- 
foundland trilobite to Olenellus instead of the genus HuUnia, as soon 
as it was published ("The Lower and Middle Taconic of Europe and 
North America, 1890"), and recalled it in his paper of 1892: "The Geo- 
logical map of theU. S., and the U. S. Geological Survey," p. 53, but to 
no purpose, so far as it concerned the U. S. Geological Survey. 
