Page:The Eurypterida of New York Volume 1.pdf/325

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THE EURYPTERIDA OF NEW YORK
319

jects twice as far beyond the carapace with five segments exposed and these segments are, as in the preceding limb, of subequal length (except the fifth which is a little longer and the seventh which is much shorter) though greatly differing in width, the fourth being more than twice as wide as the last. The second and third segments can also be seen faintly outlined in specimen, plate 56. They are only about half as long as the following, but wider; the third is still much shorter than the second, as in other eurypterids, and forms a narrow ring. The undersides of the segments are furnished with two slender spines each. The next, last limb, is again almost twice as long as the fourth in its exposed portion and the slight differences in the lengths of the segments observed in the preceding legs are here greatly exaggerated, the second and third segments being narrow rings, while the fourth segment is greatly lengthened and the fifth again longer by one third. The next two segments (sixth and seventh) are each as long as the fourth, and the eighth is reduced to nearly half that length. The segments of this limb are not furnished with spines on the underside. The coxa of this limb is also outlined on plate 56. It is relatively small, its length amounting to not more than one third of the carapace; distinctly trapezoidal in outline, width and length are subequal, its anterior margin gently convex and larger by one fourth than the posterior. The manducatory edge was apparently short. The terminal claw of the last limb is as long as the last segment and curved inward.

The metastoma has not been seen.

Genital appendages. Specimen plate 56 shows a long elliptic impression, extending over the operculum and first sternite and suggesting a female opercular appendage; and the young specimen on plate 25, figure 3, exhibits a short oval plate in the median line of the operculum.

Ornamentation. The surface sculpture shows a transverse row of sharply angular scales along the posterior margins of the segments on the upperside. Some of these along the median line of the postabdomen grew into distinct short spines. The remainder of the surface is covered with what look like smaller, more irregular, similar scales,