PART I CHAZYAN AND RELATED BRACHIOPODS—COOPER 43 
Correlation of Arline formation.—The most important elements of the brachio- 
pod faunules listed above are: Bimuria, Christiania, Eremotoechia, I sophragma, 
Palaeostrophomena, Phragmorthis, Platymena, and Titanambonites. These have 
a wide geographic distribution, and some of them have a fair stratigraphic dis- 
tribution. The Little Oak fauna of Alabama is very similar to that of the Arline 
and contains nearly all the genera and many species that are very close and a 
few identical ones. The Pratt Ferry fauna is related to the Arline and is prob- 
ably a part of the Little Oak. The Botetourt formation of Virginia, particularly 
in the Catawba Valley and on the north side of Marion, contains many of the 
same species. This is true also of the Effna formation which appears to be a 
reefy development of the Arline. Farther afield the lower Edinburg (Cyrtono- 
tella zone) of northern Virginia and the Shippensburg formation (Pinesburg 
member) of Maryland and southern Pennsylvania contain many of the Arline 
genera together with some of its species. The Arline and its correlates thus 
extend from Alabama to south-central Pennsylvania. 
It should be mentioned here that the fauna of the Benbolt formation contains 
numerous elements of the Arline fauna and is indeed the last manifestation of 
that fauna, except for its return in a modified form in the Oranda formation. 
The Tellico formation of East Tennessee for many hundreds of feet contains 
fossils in tongues of limestone or sandstone that are undoubtedly extensions of 
the Arline. It should also be mentioned that the Arline-Little Oak faunas and 
their correlates are closely related to the Stinchar-Balclatchie assemblage of the 
Girvan district of Scotland. The Oranda of Virginia is the final manifestation 
of the Arline fauna but is modified by numerous Trenton elements such as 
Cryptolithus, Rafinesquina, Calymene, Sitrophomena, and Reuschella. Elements 
of the Arline fauna such as Christiania can be found all through the Edinburg 
formation of northern Virginia. 
Athens formation.—The Athens shale was described by Hayes (1894b) as 
follows : 
East of the Tennessee River the upper part of the Chickamauga limestone is replaced by 
shales from 300 to 500 feet in thickness. Eastward beyond the edge of this sheet this forma- 
tion increases to several thousand feet in thickness, where the strata represent the rapid and 
variable accumulation of sediment near the shore. 
The formation takes its name from Athens, Tennessee, on the Cleveland sheet. 
In the description of the Athens “shale” on the Cleveland sheet the rock is 
said to be “in some places sandy, but generally calcareous, dark-blue when fresh, 
but weathering yellow.” Examination of the type section in the railroad cut 
north of Athens shows the type Athens to have only a small amount of shale 
near the base. The formation is mostly a silty or sandy, cobbly limestone that 
weathers to a yellow sandy, shaly rock. The disintegrated rock evidently led to 
the conception that the Athens is a shale. As now applied, the name Athens is 
most used for black graptolite shale, completely unlike anything in the type sec- 
tion. It is here proposed that the name “Athens” be restricted to the type region 
where the formation proves to be a facies of the Arline formation. 
At the type section of the Athens the formation rests on a thin tongue of the 
