258 SYSTEMi^TIC PALEONTOLOGY 



Description. — " Trochiform ; spire and last volution equal in height; 

 2 prominent revolving lines on last volution immediately above the aper- 

 ture, the upper one having a slight channel where it joins the volution, 

 another line near the suture and only two lines on each of the other volu- 

 tions at top and base; suture carinated; base with four large revolving 

 lines on ribs and other unequal finer lines; subumbilicated." Conrad, 

 1875. 



Shell of moderate size, solid, six-whorled; sculpture consisting of fine 

 lines of growth, of numerous elevated closely-set revolving striae and of 

 three pronounced revolving ribs — one basal on which the whorl is wound 

 and two equally distant from the sutures and with about half the width 

 of the whorl between them ; base with about nine broad raised flat-topped 

 revolving ribs with narrower interspaces between them. 



Height, 10 mm. ; diameter, 10 mm. 



Occurrence. — St. Mary's Formation. St. Mary's Eiver, Cove Point. 



Collections. — Maryland Geological Survey, Wagner Free Institute of 

 Science, Ciornell University. 



Calliostoma distans (Conrad). 

 Plate LXI, Fig. 6. 



Leiotroclms distans Conrad, 1862, Proc. Acad. Nat. Sci. Pbila., voL xiv, p. 288. 

 Monilia (Leiotrochus) distans Conrad, 1863, Proc. Acad. Nat. Sci. Phila., voL xiv, 



p. 569. 

 Monilea (Leiotrochus) distans Meek, 1864, Miocene Check List, Smitli. Misc. Coll. 



(183), p. 15. 

 Zizyphinus pimctatus Conrad, 1868, Amer. Jour. Conch., vol. iii, p. 257, pi. iii, lig. 5. 

 Zizyphinus bryani Conrad, 1868, Amer. Jour. Conch., vol. iii, p. 358, pi. xxi, fig. 9. 

 Calliostoma {Eutrochus'i distans Dall, 1892, Trans. Wagner Free Inst. Sci., vol. iii, 



pt. ii, p. 402. 



Description. — " Trochiform ; volutions 4 ; suture subcanaliculate near 

 the apex; revolving lines, a few distant, distinct, impressed, the others 

 very fine ; periphery rounded ; base convex-depressed, with six distant im- 

 pressed revolving lines and very fine intermediate lines; umbilicus nar- 

 row, profound; subcarinated at base." Conrad, 1862. 



Height, 10.5 mm. ; diameter, 11 mm. 



Occurrence. — St. Mary''s Formation. St. Mary's Eiver. 



Collections. — Maryland Geological Survey, U. S. National Museum. 



