3<DO NEW YORK STATE MUSEUM 



Dimensions. An average convex specimen measures, length 7 mm, 

 hight 6 mm. 



Habitat. Genesee province; Naples subprovince. In the Styliola 

 limestone on Canandaigua lake ; the calcareous concretions of the Portage 

 shales on Honeoye lake and from the shales in Ontario and Livingston 

 counties. Chautauqua subprovince. In the shales on Farnham creek, 

 Erie co. 



Buchiola conversa sp. nov. 



Plate 10, fig. 22 



Shell small, hinge line straight ; surface depressed convex, beak sub- 

 central, umbo not prominent, marginal outline subcircular. Surface with 

 12 or 13 ribs, which are at first flattened and at about the middle of the 

 shell become decidedly concave with elevated edges ; this concavity 

 increases to the ventral margin. Concentric striae are extremely faint on 

 these ribs. The intercostal furrows are not as wide as the ribs, and are but 

 little more concave ; they, however, have the concentric striae quite clearly 

 defined toward the anterior margin. This ornament is of quite similar 

 aspect to that of P r a e c a r d i u m d u p 1 i c a t u m, described on another 

 page, but there is no likelihood of confounding the species. Buchiola 

 conversa is quite clearly distinguished from other species of Buchiola. 



Dimensions. Length of an average example 5 mm, hight 4 mm. 



Habitat. Genesee province ; Chautauqua subprovince. Big Sister 

 and Farnham creeks, Angola, Erie co., 250 feet above the Cashaqua shales; 

 Forestville, Chautauqua co. Naples subprovince. Naples. Also in the 

 Naples fauna of Allegany county, Md. 



Buchiola angolensis sp. nov. 



Plate 10, fig. 29-33 



Shell of large size for this genus, suborbicular or slightly oval ; beak 

 somewhat anterior. Surface bearing as many as 1 7 ribs. The majority of 

 these are rounded in contour throughout their extent, but those on the 

 anterior slope show elevated marginal carinae and are slightly depressed on 

 the surface. The intervening furrows are low and narrow. The ribs are 



