Maryland Geological Survey 383 



Scaphites conradi (Morton) D'Orbigny 

 Plate XII, Fig. 1 



Ammonites conradi Morton, 1834, Synop. Org. Rem. Cret. Group, U. S., p. 



39, pi. xvi, figs. 1-3. 

 f Scaphites pulcherrimus Roemer, 1841, Verst. Norddeutschen Kreidegeb., 



p. 91. 

 Scaphites conradi. d'Orbigny, 1850, Prodr. de Paleont., vol. ii, p. 214. 

 Ammonites danw d'Orblgny, 1S50, Ibidem, p. 213. 

 Ammonites nebrascensis Owen, 1S52, Rept. Iowa, Wisconsin and Minnesota, 



p. 577, pi. viii, fig. 3; pi. ix, fig. 2. 

 Scaphites conradi Meek and Hayden, 1857, Proc. Acad. Nat. Sci., Phila., for 



1856, p. 281. 

 Scaphites conradi Meek, 1876, Rept. U. S. Geol. Survey, Territories, vol. ix, 



p. 430, pi. xxxvi, figs. 2a-2c. 



Description. — " Much compressed; one complete volution and part of 

 a second, the smaller being received into and concealed by the larger ; five 

 or six rows of tubercles on each side, the outer ones terminating at the 

 peripheral margin, the inner ones at the internal margin of the whorl; 

 tubercles united by subangular, slightly curved costas. Periphery sub- 

 convex, and marked with three or four delicate, longitudinal lines. Septa? 

 innumerable, extremely tortuous and intricate. Largest diameter nearly 

 two inches. Thickness half an inch." — Morton, 183-±. 



" Shell short-oval-subdiscoid or subcircular in outline, and rather 

 strongly compressed, often attaining a very large size ; section of volutions 

 oval, being higher than wide; inner turns closely involute and deeply 

 embracing, generally nearly rounded on the periphery ; umbilicus small ; 

 deflected part of outer volution very short, and scarcely, or not at all, free 

 at the aperture, which is oval, or with inner side more or less sinuous ; sur- 

 face ornamented with moderate-sized, straight, or sometimes slightly 

 arched costs, some of which bifurcate once or twice, while shorter ones . 

 are occasionally intercalated between the others ; costa? all passing nearly 

 straight across the periphery, but often becoming nearly or quite obsolete 

 toward the aperture on the non-septate deflected part of the outer volu- 

 tion — all occupied by the little nodes of the lateral surfaces, of which 

 about six to eight concentric rows may usually be counted on each side of 

 the volutions ; nodes of outer row around each margin of the flattened 

 periphery larger than the others, and sometimes compressed. 



