THE EURYPTERIDA OF NEW YORK. IQI 
the eyes characterize this frequent mode of preservation. In figure II the 
‘vertical pressure has acted with a slight centrifugal component, the eyes 
have wandered outward and become long, narrow and slitlke while the 
wrinkles are only found parallel to the lateral margins. In the specimen 
figure III the reverse has taken place; a component acted in a centripetal 
direction and moved the eyes inward. In this case the latter always 
appear reduced in size, the whole change producing a strangely different 
aspect of the head, which is also frequently somewhat squarish in out- 
line [pl..22, fig. 1]. In this state of preservation the margin of the head 
is frequently cut by many radiating marks indicative of the intensive 
flattening out of the outer portion of the carapace. In figure IV the pres- 
sure acted from behind and the head is folded over forward and nearly 
always shortened. In figure V, the pressure acted obliquely, so that the 
left eye is completely flattened out and the other reduced to a narrow 
crescent. The possibility of so many different expressions of form under 
pressure must be taken into account in construing specific values. 
Eurypterus megalops nov. 
Plate 83, figure 7 
Description. Carapace semicircular (width of type, 45 mm, length, 
30 mm), both frontal and lateral margins forming a continuous curve: 
posterior margin well preserved in the middle portion only, which is rather 
strongly concave; genal angles not clearly seen; eyes submarginal, of 
large size, occupying one fourth the length of the lateral margin, situated 
behind the middle line of the carapace; visual surface crescent-shaped (in 
compressed condition); eye surrounded on the outside by a distinct dumb- 
bell shaped depression; ocelli well defined, large and lving between the 
anterior portions of the lateral eyes. 
The ornamentation is obscured by the compression of the specimen; 
patches of the surface exhibit a shagreenlike sculpture which suggests 
that the better preserved fragments of integument with similar ornamenta- 
tion, found in the same beds, belong to this species. 
