Page:The Habitat of the Eurypterida.djvu/24

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THE HABITAT OF THE EURYPTERIDA

Seven specimens of Lingula sp. Hall occur on one of the slabs. Leperditia alta and a large number of pelecypods of the genus Goniophora, but labeled Leperditia alta occur on a slab which probably does not come from the Buffalo region, but is more likely from Ohio, judging from the lithological character. Finally, there are a number of specimens of Ceratiocaris acuminata associated on the same slabs with the eurypterids and showing a preservation as perfect as theirs, these being the only fossils which do show this. Number 11453 E 968 contains Eurypterus lacustris and a large specimen of Ceratiocaris acuminata, the former with head shield and body separated, but both beautifully preserved. The plant remains are important, for many of the specimens of Eurypterus are found lying embedded in Buthotrephis lesquereuxi, and in one case there is a large mass of Buthotrephis at the side and on top of a Eurypterus (13329 E 1657). (Some of these specimens of Buthotrephis are now regarded as graptolites.) There are three specimens of the plant ? form, Chondrites graminiformis, two of which are excellently preserved (13273 E 1602 and 13312 E 1641 Pohlman's type[1]). At Waterville, Oneida County, New York, a small scorpion Proscorpius osborni Whitfield has been found in a good state of preservation in the Bertie waterlime.

A remarkable fact in connection with the occurrence of the eurypterids in the Bertie is their distribution in two distinct basins or "pools," the "Herkimer pool" on the east and the "Buffalo pool" on the west. These pools, while prolific in species and individuals, have, however, only two species in common, so far as published data show. Further search may reveal more forms in common, but it is certainly a significant fact that the abundantly represented species of the two areas are distinct, when the horizon is the same, and the localities only a few hundred miles distant. The following list gives the specimens for each pool, representative or identical species being apposed (39, 92 footnote):

Buffalo Pool Herkimer Pool
1. Eurypterus lacustris 1. Eurypterus remipes
2. E. lacustris var. pachychirus
3. E. pustulosus
4. Eusarcus scorpionis
5. Dolichopterus macrochirus 5. Dolichopterus machrochirus
6. D. siluriceps 6. D. testudineus
7. Pterygotus buffaloensis 7. Pterygotus macrophthalmus
8. P. cobbi 8. P. cobbi
9. P. grandis 9. Proscorpius osborni

  1. Figured in Buf. Soc. Nat. Hist. Bull., Vol. V, p. 31 (220).