SILURIAN AND DEVONIAN LIMESTONES OF 

 WESTERN TENNESSEE. 



{Cojichided from p. jSj.) 

 C. DEVONIAN STRATA IN THE TENNESSEE RIVER VALLEY. 



II. T/ie Linden bed; Perry ville, Linden, Llorse Creek, Pyburn 

 Bbiff, White Sulphur Spring. — About half a mile northeast of the 

 railroad station at Perryville, a large quarry has been opened 

 into the top of the Brownsport bed. Immediately above is 

 found the base of the Linden limestone, with Orthothetes wool- 

 worthaims, Rhipidomella oblata, and Striatopora issa. The lower 

 third of the Linden bed, lo^ feet thick, consists of fairly solid 

 crinoidal rock with comparatively few fossils. The middle third, 

 11^ feet thick, is richly fossiliferous. It consists of softer 

 rock, partly crinoidal, partly fine-grained, and more or less inter- 

 bedded with clay. At the base of this middle division, Stropheo- 

 donto beckei, Strophonella pimctulifera, and Orthothetes woolworthanus 

 are common. Dahnanites micrurus is not rare, but Uncinuliis 

 scliudierti is very scarce. Above this Stropheodo7ita beckei horizon 

 the limestones and especially the more weathered beds and clays 

 are full of the smaller brachiopods identified from the Linden 

 bed at Perryville. The upper third of the Linden bed, about 15 

 feet thick, consists of fossiliferous clay. It is exposed in the 

 northwestern corner of the town, and is overlaid by thin layers 

 of limestone, full of bryozoans, forming a section i^ feet thick, 

 followed by a sandy bed which may be the Hardin sandstone. 

 The Camden chert fossils found at Perryville occurred loose, and 

 were apparently derived from the iron-ore gravels of Safford. 



A mile north of Linden, above the spring north of the 

 home of William H. Patton, the Brownsport bed is overlaid by 

 solid massive limestone, 5j^ feet thick, containing few fossils; 

 more shaly beds, 7^ feet thick, containing the characteristic 

 Linden bed fauna; clayey beds, 6j4 feet thick, not exposed; a 

 total of 20 feet referred to the Linden bed. Above this occurs 



679 



