Page:The Eurypterida of New York Volume 1.pdf/370

 the Buffalo Society of Natural Sciences and its posterior portion is here reproduced in text figure 76. Closer study of this indicates that again an ultimate abdominal segment has been mistaken for a telson, as the fact of its equal width with the preceding segments readily shows. The misleading bilobed aspect is produced by a strong development of the median dorsal keel which appears in this cast as a deep cleft. In the true British  the telson is nearly twice as long as the ultimate postabdominal segment.

As it would be fatuous to base a species on the manducatory edge of a coxa or even the whole coxa itself, Grote and Pitt's term  is here rejected. This is the more necessary, as these authors afterward referred to their species the free ramus of a chelicera which is clearly identical with  Hall.

Pohlman's,  ,  ,   (?) and   all belong to one species. We adopt the first name here used,, emending the species by a fuller description.

Description. Body slender, lanceolate in outline, five times as long as wide.

Cephalothorax. The carapace in mature specimens is trapezoidal, the lateral margins subparallel, slightly convex or angular, forming an obtuse angle with the slightly convex anterior margin. The posterior edge is broadly concave. The surface seems to have been uniformly convex. The compound eyes form the antelateral angles of the carapace, are subelliptic in outline and equal about one half the length of the carapace in younger and four ninths in the largest individuals.

The ocelli and the doublure are as in.

Abdomen. The abdomen does not differ in either its proportions or characters from that of. The operculum which is not well known in the latter, is here well exposed in several