The telson is furnished with small circular scales on the swollen basal part and with long spinelike scales on the remainder.
TABLE OF MEASUREMENTS OF EUSARCUS SCORPIONIS [IN MILLIMETERS]  * When marked by asterisk only the portion protruding from the carapace is measured. Approximate measurements are in parentheses. |
Horizon and localities. Remains of this species have been found only in the Bertie waterlime quarries at Williamsville and Buffalo, N. Y.
Observations. The relative size of some of the largest fragments indicates that E. scorpionis reached at least a length of four fifths of a meter or 2–3 feet and thus belonged to the larger members of the eurypterid fauna of the waterlimes. It attained at least half the size of the giants of this fauna, the two species of Pterygotus.
Lacking the long and powerful pincers of those dangerous competitors, the principal or sole organ of defense and offense must have been the telson spine. In correspondence with this important function the postabdomen is so much extended that, with the telson, it greatly exceeds
