THE EURYPTERIDA OF NEW YORK 201 
occur in other species, as in E. maria. They appear to mark the 
location of a strong muscle or muscle-bearing interior process. 
The specimen is supposed to have been derived from the greenish 
Clinton sandstones in the northern part of Cayuga county, N. Y. and is 
now in the collection of Cornell University. 
Eurypterus pustulosus Hall 
Plates 23 and 24 
Eurypterus pustulosus Hall. Palaeontology of New York. 1859. 3: 413,* 
pl. 83B, fig. 1 
Eurypterus giganteus Pohlman. Buffalo Soc. Nat. Sci. Bul. 1883. 4:41, 
le 2yatip an 
Pterygotus globicaudatus Pohlman. Ibid. p. 42, pl. 2, fig. 2 
Pterygotus globicaudatus Laurie. Roy. Soc. Edinburgh Trans. 1893. 
Nip ghia Ole Pp, Jolse yi 
Hall based his species upon a single fragmentary and rather poorly 
preserved carapace, now in the American Museum of Natural History. 
This, however, is fully 
competent to show 
the most characteris- 
tic features; the form 
of the carapace, the 
position of the lateral 
eyes and peculiar or- 
namentation. 
More than a score 
of years later, Pohl- 
man found in the 
Museum of the Buffalo 
Society of Natural Sci- Figure 39 Copy of original figure of Eurypterus gigan- 
Shake aether auch teus Pohlman, (From Pohlman) 
better preserved carapace [here reproduced in pl. 23, fig. 1] and he reck- 
lessly denoted it as E. giganteus, stating that his species had 
