J94 PALAEONTOLOGY OF KENTUCKY. 



Goinphoceras turbiniforme. MEEK AND WORTHEN. 



Plate XXI., figures 15 and 1C. 



Gomph. turbiniforme, M. and W. Proc. Acad. Nat. Sci. Phil. 1860. 

 Goynph. turbiniforme, M. and W. Geol. Kop. of 111., Vol. 3, p. 4441868. 



Shell rather small, turbinate or obovate, very slightly unsymmetrical ; sec- 

 tion circular, or nearly so ; chambered part rapidly expanding, with sides 

 slightly convex above. Non -septate part very short, or three times as wide as 

 long, rounding in abruptly, above ; aperture contracted, but exact form un- 

 known. Septa only moderately concave, nearly equidistant at all points, 

 except near the outer chamber and the apex, where they are more crowded ; 

 at about the widest part of the shell, separated by spaces equalling one-eighth 

 its greatest diameter. Siphon small and marginal. Surface nearly smooth, or 

 with only fine lines of growth. 



This description is copied from 111. Geol. Rep., Vol. 3, page 444. The speci- 

 men there described and figured on plate 12, figures 2a, b, came from the 

 neighborhood of the Palls of the Ohio. The specimens figured on my plate, 

 21, are of the average size. 



Formation and Locality. FOUR ue cherty layers superimposed upon the hydraulic limestone 

 of the Devonian formation, in Jefferson, county, Ky., and in Clark county, Ind. 



Genus Goniatites, DeHaan. 



Etymology ; yonia, an angle ; lithos, a stone. 



Goniatites discoidetis. HALL. 



Plate XX., figures 14 and 15. 



Goniatites discoideus, Hall 13th Rep. N. Y. St. Cab. 1860. 

 Goniatites discoideus, Hall. 27th Rep. N. Y. St. Cab. 1875. 

 Goniatites discoideus, Hall, lllust. Dev. Foss., pi. 71 1876. 

 Goniatites simiosus, Hall. Rep. 4th Dist. N. Y., p. 2461843. 

 Goniatites discoideus, Hall. Pal. N. Y., Vol. 5, pt. 2, p. 4411885. 



Shell depressed orbicular in the young state, becoming discoid in its advanc- 

 ing growth. It differs in size, and in the proportion of its dimensions, accord- 

 ing to its age. 



The specimen illustrated shows the average size of shells found in our 

 rocks. 



A minute description can only be given by a geologist who has a large 

 number of specimens before him, some of which he may break or cut up, in 

 order to see the number of volutions, which are all inside of the last one, or to 



