9S2 THE PALEONTOLOGY OF MINNESOTA. 



ILophosptra (?) troclioneinoldes. 

 LOPHOSPIEA PULCHELLA, H. Sp. 

 PLATE LXXIII, PIGS. 4648. 



Hight 8 to 15 mm.; apical angle 46 to 50 in the Richmond group variety 

 and 50 to 56 in the Trenton types of the species; volutions angular, six in the 

 latter and seven in the former. Peripheral band prominent, trilineate; upper or 

 subsutural carina small and close to the suture, constantly present; lower carina 

 obtuse, yet very distinctly defined by the concave band between it and the 

 peripheral keel. Base of volutions somewhat flattened; umbilicus very small, closed 

 entirely in the Richmond group variety. Growth lines as in L. perangulata and 

 L. medialis, from both of which it is readily distinguished by the upper carina, those 

 species being without that feature. 



The development of an upper carina brings this species into closer relations 

 with L. oweni and L. saffordi than it holds with the two species mentioned in the 

 foregoing paragraph. The absence of the umbilical swelling and the small size of 

 L. pulchella will of course suffice to distinguish it specifically from these. L. 

 spironema and L. tenuistriata are exceedingly like it to the unassisted eye, but with 

 the aid of a magnifier good specimens may be distinguished at once by their surface 

 markings, the present species having lines of growth only, while both of the others 

 have revolving lines as well. L, pulchra McCoy resembles this species very greatly, 

 yet, relying on the accuracy of McCoy's illustrations, we see at once that his species 

 is a member of the Bicincta section and not, as is the case with L. pulchella, of the 

 Perangulata section. Indeed L. pulchra seems to be uncomfortably near certain 

 varieties of L. bicincta. 



Formation and locality. Upper part of Trenton crroup, Burgin, Danville and Frankfort, Kentucky; 

 Black River group, Ctenondonta bed, near Cannon Falls, Minnesota; Richmond group, Spring Valley, 

 Minnesota. (Over 30 specimens.) 



Collections. Geological and Natural History Survey of Minnesota; E. O. Ulrich. 

 Museum Begister, No. 7383. 



LOPHOSPIEA SAPFORDI, n. sp. (Ulrich) 



Pl.LKMIfFWI-Jrh 



Hight 23 to 33 mm.; apical angle 59 to 65. Volutions seven, very 

 angular, the peripheral band unusually prominent, upper and lower keels both 

 distinct; upper carina removed a third of the width of the upper slope from the 

 suture; surface of whorl lying between the three keels decidedly concave; umbilicus 

 small, rather abrupt, the surface between it and the lower carina either flat or 

 slightly concave. Aperture quadrate, or it might be called subtriangular, moder- 

 ately produced below, the inner lip nearly vertical, broadly reflexed. Surface 

 markings consisting of unequal sublamellose lines of growth, sweeping backward 

 very strongly to the peripheral band. 



