Strophia fastigata Maynard, 1896

Original Description


Tapering Strophia.

Plate II fig. 1, front, fig. 2, side view of type.


         SP. CH. Size, medium. Shell quite thick. Striations, present.

Whirls, 10. Examined 62 specimens.

Form of shell, a pointed cylinder with the first whirl the largest, the next four are each successively a little smaller, then the shell slopes abruptly to a somewhat obtuse point, forming an angle of sixty-two degrees There are nineteen striations on the first whirl, not very promi­nent, not very regular, and not arranged in lines. They are not fur­rowed on top, but are smoothly rounded and polished.

Aperture about as high as wide rather large and open, being considerably wider at the entrance than further within. Lower tooth small about .04 long by .02 high. It is about central in position, and is placed far back in the shell at about three times its length from the frontal bar. The upper tooth is about the same height as the lower.

Margin, not produced forward as far as the diameter of the shell, is very slightly inclined to the right and a little beyond the side, but is extended outward about .05 and slightly rolled backward and the edge is rounded. The frontal bar is quite well developed, is somewhat obliquely inclined and almost completely interrupts the striations which are slightly indicated only within.

Color of shell, externally, white without markings; internally, pale yellowish brown, fading into white on the margin.


         Size of type 1.20 by .40. Largest specimen, 1.25 by .42; smallest,

1.10 by .35. Longest; 1.20; shortest, 1.10.


     Young specimens with the margin fully formed, but in which the frontal bar is not fully developed, do not have the teeth. There is very little individual variation, some shells being a little more obtuse than the type, but there is a form as given below.

     Form No.1 with fewer striations, these being mainly absent on all but the upper three whirls, where they are finer and more numerous. about 28 to the first whirl. There is in many instances in this form a distinct double lower tooth. There is also an inclination in some speci­mens of the type form to assume a double lower tooth.

This species may be distinguished by the rather large aperture, pointed cylindrical form of the shell, comparatively small size and white, unflecked color.

This species I found in the collection in the same tray with the shells which I have named S. scripta obliterata, therefore it is to be presumed that they came from Matanzas, Cuba, but as all of the shells of S. fastigata are deeply stained with a red earth of which those of S. s. obliterata bear no trace, it is evident that they did not come from the "rocks close to the sea" as did the others, but probably from some neighboring field. They were also labled  "Pupa chrysalis. Another

lot was labeled " Punte Gorde, Matanzas, Pupa infanda," and still

another lot" Chorrea, Pupa mumia.""

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