GENUS LOXONEMA. 367 



GENUS LOXONEMA (Phillips). 



LOXONEMA LEDA(n.s.). 

 PLATE 15 (6), FIG. 2. 

 Loxonema sp., page 346 = p. 42 of original paper. 



Shell turreted. Spire rapidly ascending, composed of eight or more volu- 

 tions, which are moderately convex on their surfaces, a little more ab- 

 ruptly rounded below the middle, and very gradually increasing in dia- 

 meter; suture close, not very distinctly marked; apicial angle about 

 twenty degrees ; columellar side of aperture elongated or pointed. Other 

 characters of aperture unknown. 

 Surface characters obscure ; faint indications of transverse ridges crossing 

 the larger volutions exist in the matrix. 



This species was originally compared by me (loc.cit.) with L.Jitchi, to 

 which its imperfect casts bear some resemblance; but a critical examina- 

 tion shows it to be a very distinct species. The species referred by Prof. 

 WiNCHELL to L. suhulata is apparently identical with L. leda, judging 

 from a cast of the upper volutions communicated by him. It is, at any rate, 

 very distinct from L. i^ubulata, the spire being much less rapidly ascending. 

 Formation and locality. In limestone of the age of the Niagara group, 

 at Wauwatosa, Wisconsin, and Bridgeport, Illinois. 



Among the collections from Wauwatosa, Waukesha, Kacine and other 

 localities of the Niagara group in Wisconsin, there are remains of other 

 species of Gasteropoda than those here described ; but their condition is 

 such, that for the most their description or illustration would add little to 

 our positive knowledge of the subject. The description of the interior 

 casts of species of this class of fossils is usually even less satisfactory 

 than that of other fossils in a similar conditien ; but as it seems unlikely 

 that we shall get them in any other, we are compelled to make such use of 

 them as will aid in further comparisons of the fossils of these rocks from 

 other localities. 



