Strophia obscura Maynard, 1896

Original Description

"66 STROPHA OBSCURA. Novo.

Obscure Strophia.

Plate III, fig. 5 front, fig. 6, side view of type.

DESCRIPTION.

SP. CH. Size medium. Shell rather thick and heavy Striations, absent. Whirls 9, the upper of which is about equal to all of the others put together. Examined 50 specimens.

Form of shell, a pointed cylinder, with the first two whirls equal in diameter, from this the shell slopes to a rather acute point, forming an angle of about 50 degrees. The shell is quite smooth, marked with faint and irregular lines of growth, which scarcely assume any prom­inence even on the upper whirl. The whirls are not bulging and the suture is shallow.

Aperture of medium size, quite open and slightly contracted with in. The lower tooth is small, about .04 high, about twice as long as high; is single, is set back at least twice its length from the frontal bar, and is situated a little to the right of the centre. The upper tooth is about as high as the lower, but extends back around the column, is set well back, begining about in the middle of the lower, but is not set high up on the column

The margin is not produced forward beyond the diameter of the shell, is slightly inclined back at the top, and a very little to the right, scarcely beyond the diameter of the shell. It is a little thickened, about .05 ) is rolled over and reflexed outward a very little, ( about .03 ) and the edge is smoothly rounded. The frontal bar is quite well developed, but is not much inclined.

Color of shell externally, bluish white, obscurely marked with zig­zag, longitudinal lines of very pale yellowish brown. These markings are scarcely to be seen with the unaided eye on the upper portion of the shell, but are a little better developed on the spiral whirls, where they are rather more regular and numerous. Internally, flesh color becoming white on the margin.

DIMENSIONS.

Size of type 1.10 by .42. Largest specimen, 1.15 by .50; smallest .98 by .40. Longest specimen 1.15, shortest, .98. Greatest diameter .45, smallest, .40.

OBSERVATIONS.

Some specimens are proportionately shorter than others and there are rather more markings on some than others, many being less marked than the type. There is one well defined form as given below.

Form No. 1. More slender and more cylinderical than the type the first three whirls being about equal in size, 1.05 by .43. The suture between the whirls are quite shallow and there are few fleckings which are confined to the lower four or five whirls.

            I found these shells in the collection labeled" Pupa sagraiana Pfr.,

Cayo Birde del Norte, Cuba."

This is not the Pupa sagraiana of Pfeiffer, however, as can be read­ily seen by reading his description with care. He says distinctly that sagraiana is elegantly marbled, that there are narrow striations, besides his shell was much smaller, not quite an inch long, and very slender, about .40 in diameter. It was also a differently proportioned shell as the aperture was as wide as the diameter of the shell, and very nearly as high, thus the shell was at least one fourth shorter than any specimen of S. obscura that I can find, but the aperture was fully as large.

Further on, he gives a larger form calling it Beta major, says that it is marbled with fuscous and smooth, but the size of this is given as 26 mill. by 10 mill. This is much too small for any shell of S. obscura. Pfeiffer's types of P. sagraiana came from Cayo Galinda, Cuba where he says Dr. Gundlach found it common, and it is probable that we shall have to see shells from that place before we find the true P. sagraiana."

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