THE EURYPTERIDA OF NEW YORK 175 
The chelicerae are seen in position in one specimen. The pincers are 
partly lost and partly obscure,-but the full length of the basal joints 
is shown. A well preserved chelicera exhibiting a broader free blade with 
slightly curved tips and a narrower straight finer blade is shown in another 
example. The basal joint is twice as long as the blades and rather slender. 
This chelicera measures about three sevenths the length of the meta- 
stoma. A third detached chelicera, finely exhibiting the blades, is repro- 
duced in plate 12, figure 1. Here the basal joint is broad and relatively 
short. | 
The four pairs of endognathites do not differ from those of E . remipes. 
The first three pairs are relatively short and stout; they increase 
in length from the first to the third pair at such a rate, that in their usual 
position their extremities form a straight line nearly tangent to the front of 
the carapace [pl. ro], the third being about twice as long as the first. The 
middle segments of the first endognathite are about one third wider than 
long, those of the third as long as wide. The spines of these endognathites 
are long and slightly curved and those of the posterior sides slightly longer 
than those of the anterior. The fourth pair of legs is longer than the pre- 
ceding pair by one half and slightly more slender. The last clawlike seg- 
ment is very strongly developed. The coxa of none of these endognathites 
has been seen fully exposed; nor has the epicoxite been observed. 
The swimming legs are broad and powerful organs, though subject to 
some variation [see var. pachychirus|]. They reach to the sixth 
tergite when reflexed. The coxa [pl. 11, fig. 5] is correspondingly large 
and strong. In form it does not differ from that of E. remipes. 
The second to the sixth segments are also like those of that species. The 
seventh segment which with the eighth forms the paddle is much widened 
and trapezoidal in outline; its length and width about equal; the posterior 
side straight or slightly convex, the anterior highly convex, the distal 
margin straight, with a large subtriangular guide plate for the eighth seg- 
ment attached to it. The eighth and ninth segments are as in the pre- 
ceding species. 
