2&2 C. A. Reeds — Hun ton Formation of Oklahoma. 



Lithology. — Along Chirnneyhill creek this formation is com- 

 posed of bluish to yellowish, thin to moderately thick bedded 

 earthy limestone and intercalated shale beds in the lower L80 

 feet, while the upper 43 feet is of white marly bods. In the 

 type area, and also in the vicinity of Dougherty, alternating 

 yellowish shales, shaly limestones and bands of reddish earthy 

 limestone occur. The lower 180 feet of the Chirnneyhill sec 

 tion is represented thus in the Henryhouse creek section. 

 Faunally, it contains many of the same species but is less pro- 

 lific in the number of individuals. The white marly beds and 

 their coral fauna are not present at the top of the Henryhouse 

 creek section. As ma} 7 be seen the beds of the two sections are 

 thus somewhat variable in character as well as in thickness. 

 The sediments were evidently deposited in shallow oscillating 

 seas which bordered an irregular coast-line of slightly uplifted 

 land, or, possibly in a sea containing scattered islands. 



Fauna. — The fauna of the Henryhouse shale is more pro- 

 lific than that of the Chirnneyhill formation below, although 

 fossils are scant in the lower 120 feet. They may be collected, 

 too, with greater ease from the weathered shale slopes of the 

 Henryhouse than from the hard limestone ledges of the 

 Chirnneyhill. The contact between these two formations is 

 sharper in the northeast part of the mountains in the Lawrence 

 anticline, than in the vicinity of Dougherty and along the 

 south side of the mountains, west of the Washita river. The 

 fossils from the lower 120 feet of this formation correspond 

 more closely to those of the Bob formation of Tennessee and 

 this division may be known as the Lower Henryhouse. The 

 fossils from the remaining 102 feet correspond most closely to 

 the Lobleville beds and these beds represent the Upper Henry- 

 house. It may thus be seen that the unconformity between 

 the Chirnneyhill and Henryhouse formations is denoted by the 

 absence of the Osgood, Laurel, Waldron, Lego, Dixon and 

 Beech river formations as defined by Pate and Bassler.* The 

 names and stratigraphic range of the diagnostic species of the 

 Henryhouse formation are as follows : 



Characteristic Species of Henryhouse Formation (Silurian). 

 Lower Henryhouse. 



Glassia sp., Scenidium i?isir/ne, Schicchertella n. sp., Strophe- 

 odonta n. sp., Strophonella prolongata, Platyschisma n. sp., 

 Orthoceras n. sp., Bronteus cf. plana, Ceraurus niagarensis, 

 Dalmanites n. sp., JSncrinurus n. sp. 



*Pate, W. F. and Bassler, E. S., Proc. U. S. Nat. Museum, vol. xxxiv, 

 p. 410. 



