THE EURYPTERIDA OF NEW YORK 207 
more prominent than in.the other two specimens. This specimen also 
demonstrates that the scalloping of the edge of the carapace is due to the 
presence of scales. | 
The National Museum contains a fragment [pl. 23, fig. 2] of a very 
large carapace of this species from the waterlime at Buffalo which indicates 
that the species must have attained much larger proportions than any 
other known Eurypterus. This carapace was approximately 250 mm 
wide in front of the eyes, to whicha basal width of about 300 mm 
and a length of the carapace of about 160 mm would correspond. The 
whole body must have measured fully one meter. 
There is no species of Eurypterus which this form closely resembles, 
and it must represent an aberrant branch of the genus, if, indeed, it actuallv 
belongs in the genus at all. Only the carapace and the postabdomen of 
the animal are known and the appendages may prove to be quite different 
from those of Eurypterus. In this connection it is suggestive that the 
Scottish representatives of Laurie’s genus Drepanopterus possess some 
of the features in which E. pustulosus differs from typical Euryp- 
terus [Laurie. 1892, pl. 3, fig. 16; 1899, pl. 3, fig. 17; pl. 4, fig. 22]. 
Drepanopterus pentlandicus exhibits strong “granular mark- 
») 
ings ’’ which, judging from his figure [pl. 4, fig. 22], may well resemble those 
of E. pustulosus in size and distribution, while in D.lobatus 
_ the posterior angles of the postabdominal segments are produced into like pro- 
cesses. On the other hand, E. pustulosus_ does not possess the 
characteristic form of the carapace of the Drepanopterus-Stylonurus group 
and in the lobation of the postabdominal segments and its strong orna- 
mentation, it suggests the last Carbonic representatives of the race, notably 
E. mansfieldi Halland E. (Anthraconectes) mazonensis. 
Eurypterus pristinus nov. 
Plate 83, figures s, 6 ’ 
Description. Carapace broadly subrectangular, about one half longer 
than wide (width, 20.5 mm, length, 13.5 mm). Anterior margin slightly 
