MARYLAND GEOLOGICAL SURVEY 309 



the inner lip is thin and folded over so as to conceal the minute umbilicus. 

 Surface finely striated. Length about 30 lines; width of body whorl 

 15 lines. 



This species is about the size and somewhat of the shape of M. belli- 

 cincta. The principal difference is in the form of the upper part of the 

 whorl. The lower two-thirds or three-fourths of the whorl is nearly 

 uniformly convex, but the upper third descends abruptly to the deep 

 suture. The band is quite flat, and being situated on the upper sloping 

 part, gives to the whorl a truncated appearance. The lower edge of the 

 band is defined by a small acute carina, seldom visible in specimens which 

 are worn." Billings, 1865. 



Occurrence. CHAMBERSBURG LIMESTONE (Tetradium cellulosum bed) . 

 Fort Loudon, Franklin County, Pennsylvania. Lowville limestone of 

 Canada and Kentucky. 



Collection. U. S. National Museum. 



Family BUCANIIDAE 



Genus BUGANIA Hall 

 BUCANIA SULCATINA (Emmons) 



Plate XXXIX, Figs. 6-8 



Bellerophon sulcatinus Emmons, 1842, Geol. Nat. Hist. New York, vol. ii, 



p. 312, text fig. 4. 

 Bucania sulcatina Hall, 1847, Pal. New York, vol. i, p. 32, pi. vi, figs. 10, lOa; 



pi. xxxiii, fig. 4d. 

 Bucania champlainensis Whitfield, 1897, Bull. Amer. Mus. Nat. Hist., vol. ix, 



p. 181, pi. iv, figs. 14-16. 

 Bucania sulcatina Raymond, 1908, Ann. Carnegie Mus., vol. iv, p. 194, 



pi. xlix, figs. 15-17; pi. 1, figs. 3, 4; pi. Iv, figs. 13, 14. 



Description. " Shell large, coiled in one plane, umbilicated on both 

 surfaces, all the whorls visible. The whorls are broad, somewhat angular 

 at the sides, the last whorl moderately expanded at the mouth. Shell on 

 the whorls thin, but on the lip it becomes very thick and sometimes corru- 

 gated. The surface is ornamented by coarse wavy revolving striae which 

 are crossed by transverse lines of growth. 



