922 THE PALEONTOLOGY OF MINNESOTA. 
[Bucanopsis. 
this species sometimes look very much as though they might be a larger variety of 
Protowarthia granostriata. Yet this is most certainly not the case, since the species 
possesses a slit-band and the aperture of a true Bellerophon. When neither of these 
features is preserved, then it is distinguished from the Protowarthia by its open 
umbilicus and larger size. 
Formation and locality—Lower part of the Loraine group and upper part of the Utica group at 
several localities in the vicinity of Cincinnati, Ohio. 
Collection.—H. O. Ulrich (7 specimens). 
Genus BUCANOPSIS, n. gen. 
Bellerophon (part.), HALL, MEEK, DE Koninck, McCoy, D’Orxsiany, and®ther authors prior to 
1880. LinpDsTR6m, 1884, Silurian Gastropoda of Gotland. 
Bucania (part.), WAAGEN, 1880, Paleeontologica Indica, ser. 13, pt. 2, pp. 1830 and 150. KoxkeEn, 1889, 
N. Jahrbuch f. Mineralogie, etc., Beilageband vi, p. 379. 
? Huphemus (part.), McCoy, 1844, Synopsis Carb. Foss. Ireland, p. 25. 
For generic characters see page 853. 
The greater part of the species which we propose to classify under this generic 
name were originally described as of Bellerophon, an arrangement that was quite 
satisfactory to paleontologists till 1880 when Waagen proposed to separate them on 
account of their spiral surface sculpture. In this we think he was fully justified, 
because extensive studies of the Bellerophontacea prove conclusively that the surface 
markings deserve a high rank among the characters that are available to the 
systematist who seeks to subdivide the group into natural and convenient generic 
sections. But, as we shall show in discussing that genus, both he and Koken, who 
adopts Waagen’s proposition, are wrong in extending the application of Hall’s 
Bucania to all the spirally striated bellerophontids. Bucania must be restricted to 
species of the type of B. sulcatina, which is quite different in other respects from the 
Devonian and later Paleozoic shells that make up the bulk of the species referred 
by them to Hall’s genus. The surface markings even are not exactly the same in 
the two groups, they being straight and parallel with the direction of the whorls in 
Bucanopsis while in true Bucania they are wrinkled, interrupted and more or less 
oblique in direction. 
It seems very clear to us that Bucanopsis was developed from Bellerophon and not 
from Bucania. Every character of the genus, excepting the revolving lines, corres- 
ponds with the former and is more or less different from the latter. A comparison 
of the figures of species described in this work alone can scarcely fail to convince 
students that this is really a fact, and the same must continue to grow more obvious 
when they extend their comparisons to Upper Silurian, Devonian and Carboniferous 
Bellerophontide. 
