GASTROPODA. 1061 



bum*mum 1 



CYCLONIC* A HUMBBOSUM, n. up. (Ulrich.) 



PLATE LXXV1II. KI38. U- 



Th- average site la this specie* U somewhat greater than In clth.-r i.f the preceding form*, while the 

 apical angle It generally wider and more constant, the majority of the specimens Tarylng comparatively 

 imt httl<> >-uh<T way fn.in 86. The principal feature, however, Is a strongly developed shoulder, giving a 

 deeper suture than In any other species of the genus. This shoulder may be rounded or, especially In tli<> 

 Rlrhiuntid group form, quite angular. In the latter the slope of the outer side of the last whorl Is very 

 nctly concave, and not Infrequently undulated In the direction of the line* of growth. The 

 same conditions occur less frequently though quite as well marked In the Lorraine form. The surface 

 marking* are fairly constant. About ten principal subequal earlna- occur on the outer slope of the body 

 whorl, and about the sam<> number of smaller ones on the periphery and base-. The larger ones usually 

 alternate with a much thinner set. 



Formation and locality. Very abundant In the upper half of the Lorraine group at Cincinnati, and 

 not rare at several horizons In the Richmond group, at Waynesvllle, Clarksvlllc, Oxford and other locali- 

 ties In Ohio. Also at Richmond, Versailles and other points In Indiana. 



Cblfcdion.-E. O. Ulrich. 



CYCLONKMA PYRAMIDATCH James. 



I'l.ATK. I. XX VII I. FIGS. a and M. 







Oydonema pyramidala JAMES, 1874, Gin. (juar. Jour. Sri., vol. I., p. 152. 



In Ite typical form It Is scarcely possible to confound this specie* with any other known, but there 

 are varieties, one of which shows Its derivation from (7. madtol* the starting point for most of the Cin- 

 cinnati species of Cyeioxema while another develops a shoulder at the top of thf whorls, causing It to 

 reneoible C. humervium. One of the best characters Is the extension of the spiral strlatlon over the entire 

 base. In roost of the other forms the spiral lines extend only about half across the base, the Inner part 

 having transverse stria- only. 



Formation and locality. Lorraine group, Cincinnati and vicinity. 

 CMbetoik-R. O. Ulrich. 



CYCLONEMA HIMITLANS, n. sp. (Ulrich.) 



PLATE LXXVI1I. flO 47. 



Of this species we have about fifty specimens. These show that the shell Is of medium size, with a 

 general form about Intermediate between C. humerotum and C. medinle, though rather nearer the former, 

 there being usually a small shoulder and a flattening or even a (light concavity of the outer slope of the 

 last whorl. It is distinguished from both by Its surface markings. These consist as usual of revolving 

 and obliquely transverse lines, but the former are much weaker on the last two whorls and often quite 

 obsolete near the mouth, while the latter are more distant excepting In the last third of the body whorl 

 of old examples. In the latter the mouth is sometimes irregularly expanded and thrown upward along the 

 suture. 



Formation and locality -Upper division of the Lorraine group at Cincinnati, Ohio. 

 .-E. O. Ulrich. 



