ART. 21 ORDOVICIAN TEILOBITES ULEICH 47 



dian Lecmiospira zone on Indian Creek, one and a half miles south- 

 east of Bluff City, Tenn. 



Holotype.— Cat. No. 80550, U.S.N.M. 



STRATIGRAPHIC AND GEOGRAPHIC RANGE OF TELEPHUS AND 

 CORRELATION OF FORMATIONS 



Range cmd origin of Telephus faunas. — In the Appalachian Valley 

 remains of Telephus are confined to areas in the eastern half of the 

 valley south of Staunton, Va., and in the north to a few places in 

 southeastern Canada. All these occurrences are in faunas that are 

 clearly of Atlantic (Poseidon) origin. This conclusion is based 

 mainly on two facts : First, that Telephus and nearly all of the re- 

 mainder of the faunas in which species of this genus of trilobites 

 occur are wholly absent in the Ordovician deposits in most of the 

 western half of the Appalachian Valley. The latter, on the other 

 hand, agree in lithic and faunal characters with the Ordovician de- 

 posits in the Ohio Valley. Second, the faunas of the Blount group, 

 which include species of Telephus and many other genera that are 

 found in America only in the eastern belts of the Appalachian Val- 

 ley, are represented by very similar and in some cases perhaps in- 

 distinguishable species in related and in part perhaps contemporane- 

 ous formations in southeastern Canada, Scotland, Norway, Sweden, 

 and Bohemia. 



In Virginia, Tennessee, and Alabama the first appearance of 

 Telephus is in the Whitesburg limestone. It is this formation also 

 that gave us 8 of the 15 or 16 species described in this paper from 

 southern Appalachian localities. Of the remaining species five came 

 from overlying Athens shale and three from the succeeding Tellico. 

 The vertical range of the genus therefore seems as well fixed in the 

 sequence of Upper Chazyan deposits in the Appalachian Valley as 

 in its geographic range. Further, in view of its restricted occurrences 

 in the St. Lawrence Valley and Newfoundland and, on the other 

 side of the Atlantic, in southern Scotland, Sweden, Norway, and 

 Bohemia it seems fairly clear that the type originated in and dis- 

 persed from the middle Atlantic basin. 



In America, as in northeastern Europe, Telephus is often associated 

 with species of such other genera of trilobites as Ampyx^ Loncho- 

 domus, Ampyxina, Ro-bergia^ Remopleurides, Dionide, SalteHa, 

 T7'inucleus, Bronteopsis, and Nileus, all of which I regard as also 

 indigenous to the middle Atlantic Basin. None of them has been 

 found in Cordilleran faunas or Chazyan or younger Ordovician ages 

 that were developed in the Arctic and Pacific realms nor in the 

 Ordovician faunas in the Mississippi and Ohio Valleys that are 

 thought to have invaded the continent from the south. Nor have 

 they been found in the typical Chazyan in the Champlain Valley or, 



