REPORT ON PAL^ONTOLOGICAL COLLECTIONS. 363 



GASTEROPODA. 

 Genus PYRGULIFERA, Meek. 

 Pykgulifera humerosa, Meek. 



Plate 5, fig. 6, a, b, c. 

 Mihinia huuierosn, Meek (July, 1860), Proceed. Acad. Nat. Sci. Philad., XII, 313. 



I'l/n/nli/, ra hnnun^n, M, .k ( 1S7-J), in Hayden's Second Ann. Report U. S. Geol. Survey of the Territories. •*><♦. 



Shell rather thick, subovate; spire conical, moderately- elevated: volutions about 

 five and a half, distinctly shouldered, and more or less angular, last one comparatively 

 large, rounded and contracted below; suture distinct: surface ornamented b\ about 

 fourteen rather strong, regular, vertical folds or cost.-e to each turn: folds obsolete on 

 the lower part of the body-whorl, but becoming more strongly defined at the shoulder, 

 where they often terminate in very prominent nodes, so as to give the whorls a distinctly 

 coronate character: crossing these folds or cost;e, there are on each volution of the 

 spire about four, and on the last whorl some seven or eight, regular, equidistant revolv- 

 ing lines, or small ridges. 



The specimens of this interesting species are too imperfect to afford accurate 

 measurements, but some of them appear to have been, when entire, about 1 inch in 

 length, and 0.60 inch in breadth. One individual (see fig. (i h, plate v), apparently of this 

 species, shows the aperture to be narrow-oval. On this specimen, which consists of 

 scarcely more than the body-whorl, the costa- do not terminate above in as prominent 

 nodes as in others, but merely form small tubercles at the shoulder, which is more 

 sloping than in most of the other specimens. 



This species bears considera hi e resemblance to Jfr/ai/opsis anuafa of Matlicroii 

 (which seems to be a Melanin or Tiara), from the Tertiary Lignite formations at the 

 mouth of the Rhone (see Cat. Method. Corps Org. Foss. Depart, des Bouches-du-Khone, 

 plate 37, fig. 12), but differs in having the folds or costa- more distinct, and developed 

 on the whorls of the spire as well as on the last volution. These costa' also in the 

 species under consideration differ in terminating in rounded prominences, while upper 

 ends of the French species seem to be flattened horizontally, and its revolving lines are 

 much more numerous than those of our species. 



Long after writing the above, I had an opportunity to examine hundreds of speci- 

 mens of this shell, and in a very few^ examples I succeeded in seeing the aperture and 

 columella very clearly. The inner lip is more thickened, and the margin at its base 

 more effuse, and the aperture more angular there than as shown in the figure of the 

 imperfect specimen represented by our fig. 6 h, plate v. I have had to establish a new 

 genus for its reception, as it is certainly not a Melania, nor a Tiara, to which latter I at 

 one time believed it might belong. 



Locality ami iiosit'arn. — Same as foregoing. 



LiMN^EA nitidula, Meek. 

 Plate 5, fig. 14. 

 Mtlanla ? nitidula, Meek (July, 18(50), Proceed. Acad. Nat. Sci. Philad., 314. 



Shell subovate; spire conical, moderately elevated; volutions about six and a 

 half, rounded-convex, increasing rather gradually from the apex; suture well defined; 



