Maryland Geological Survey 145 



occurrence in the same zone in Pennsylvania and New York. The upper 

 crinoid bed is not exposed though many crinoid stems were found in the 

 talus in the upper portion of the section. Fear the middle of the Keyser 

 member the limestone beds are very shaly and contain the same bryozoan 

 faunules as at Devil's Backbone. Above the bryozoan fauna come the 

 heavy, massive dark blue limestones of the middle beds of the Keyser 

 member. 



The section of the Keyser member at this point is not so good as that 

 at the Devil's Backbone. However, the principal fossil zones are exposed 

 and while much of the section is covered by talus, yet the latter furnishes 

 a large number of well-preserved fossils, so that this is one of the best 

 collecting grounds for fossils of the Keyser member in Maiyland. 



The section begins at the bottom of the lowest Stromatopora bod of the 

 Keyser in the limestone quarry at Cash Valley. In addition to Stromato- 

 pora constellata this bed contains crinoids (aa), Cyathophylluin schu- 

 clierti, Favosites hclderbergia' var. prcecedens. 



Heldeeberg Formation 



Horizontal 



Keyser Member '''fp^t"^*^ 



Thin-bedded gray limestone, heavy-bedded at top. 

 At the bottom occur Stropheodonta varistriata (r), 

 Calymene sp 137.1 6.8 130.4 



Blue-gray heavy-bedded limestone becoming dark 

 blue near the bottom, beneath which the limestone is 

 cherty 130.3 18.0 123.6 



Thin-bedded cherty limestone 112.3 2.0 105.6 



Heavy-bedded grayish-blue limestone. At the bottom 

 occur Atrypa reticularis (r) 110.3 3.0 103.6 



Thin-bedded gray-blue limestone. At bottom occur 

 Dalmnnella sp., crinoids (c), Orthopora rhombifera, 

 Stromatotrypa globularis (c), Stenochisma sp. (r). 

 This is the first occurrence of bryozoa in the section. . . 107.3 3.8 100.6 



Thin-bedded limestone becoming more argillaceous 

 towards the bottom. Near the top occur crinoids, 

 Batostomella interporosa, LHplostenopora siluriana, 

 Fisluliporella tinni/huidica, F. micropora, Orthopora 

 rhombifera. PliUidu t un tim'Ua. Leptcrna rhomboidalis 

 (r), Camarotu'cJiiu Utrttflrldctisis. This is the first 

 prolific bryozoan layer 103.5 4.5 96.8 



10 



Vertical 



Total 



thicknes 



s vertical 



feet 



thickness 



