208 NEW YORK STATE MUSEUM 
convex, antelateral angles well rounded, lateral margins nearly parallel, 
slightly concave in the middle and curving outward toward the genal 
angles which are slightly produced sideways; posterior margin nearly 
straight transversely; eye nodes subcircular, small (about one seventh the 
length of the carapace), situated just forward of the center and twice their 
diameter from the lateral margin; the form and size of the visual surface . 
have not been made out. 
The surface of the type specimen exhibits, especially on the posterior | 
portion, low, rather broad nodes, so closely arranged as to be in contact 
at their bases. A body segment lying close to the carapace possesses a 
similar ornamentation. 
Patches of integument are found associated with the eurypterids at 
Schenectady which present the aspect of a shagreen, their surface being 
covered with low, flat nodes which in many places become so crowded that 
they assume polygonal outlines. We consider it probable that these 
patches belong to this species. | 
Horizon and locality. Frankfort shale. Dettbarn quarry, Schenectady, 
N. Y. | 
Eurypterus ranilarva nov. 
Plate 17, figure 7; plate 18, figure 2 
Description. Body of small size, very plump in general appearance, 
the carapace and preabdomen forming a broad oval from which the post- 
abdomen is set off rather abruptly. 
The carapace is strikingly broad (length : width as 5:7) and nearly as 
wide as the broad preabdomen; subrectangular in outline; anterior margin 
straight to slightly emarginate in the middle and rounded at the anterior 
corners; lateral margins gently convex, slightly contracted toward the pos- 
terior angles; its doublure remarkably broad, forming a wide rim (4 mm) 
that gradually narrows along the sides; it bears a deep broad furrow in the 
middle that ends somewhat abruptly just behind the anterior corner, and 
fine parallel striae on the flat portion outside of the furrow; along the 
‘inner edge of the furrow runs a narrow crest. The rim seems to have been 
