NAPLES FAUNA IN WESTERN NEW YORK, PART 2 319 



concave surface covered with retrally curved striae. On the upper surface 

 of the whorls is a single revolving elevated line between the suture and the 

 slit band. This is obscure on early whorls, becomes more prominent in 

 later growth, but is again obscure at full growth ; faint trace of a second 

 revolving ridge may sometimes be observed. The surface is crossed by a 

 multitude of fine, hairlike, elevated concentric lines, which are raised into 

 small nodes at intersection with the revolving ridge, but between the latter 

 and the slit band are greatly obscured or lost. On the lower surface of the 

 outer whorl the fine concentric lines are closely crowded together and are 

 crossed by four to six very obscure revolving ridges. 



Dimensions. An average example has a hight of 8 mm and diameter 

 of 7 mm. 



Habitat. Genesee province ; Naples subprovince. Common as 

 replacements in the concretions of Whetstone gully, Conesus lake, and on 

 Honeoye lake. 



Pleurotomaria genundewa sp. nov. 



Plate 19, fig. 33, 34; plate 20, fig. 1-7 



Shell having the dimensions and outline of P. ciliata, from which it 

 differs in the character of its ornament. These shells have a narrow slit 

 band and bear two well defined and subequal revolving ridges on the upper 

 surface of the whorls, both of which are knotted by intersection with the 

 concentric elevated lines, the latter being much coarser and fewer than in 

 P. ciliata. On the lower surface of the whorls the concentric lines are 

 quite strong and distant, with intercalated additions near the slit band ; 

 these are crossed by five or six revolving lines, but. the intersections are 

 not sharply knotted. 



Habitat. Genesee province ; Naples subprovince. Very abundant in 

 places in the Styliola limestone. On Canandaigua lake and at Middlesex, 

 Yates co. N. Y. 



