Dolichopterus otisius Clarke
D. stylonuroides nov.
Stylonurus (Ctenopterus) cestrotus Clarke
S. (Ctenopterus) sp. α, sp. β, sp. γ
S. myops Clarke
S. sp.
Hughmilleria shawangunk Clarke
Pterygotus globiceps nov.
of black shale of the Shawangunk grit with indeterminable patches suggestive but not demonstrative of eurypterid integument. (See Appendix).
From the National Museum are three lots. The first, two split pieces of one slab of waterlime, is from the Salina of Selinsgrove Junction, Pa., and exhibits segments which suggest an Eurypterus, like E. remipes. This occurrence was recorded by Schuchert in 1903 [Lower Devonic and Ontaric Formations of Maryland, p. 416]. In character of the rock and the association of these remains with large Leperditias this slab is very like the Bertie waterlime.
The second lot consists of "black shale interbedded in the Keefer sandstone member of the McKenzie formation (basal Cayugan), Lock 53, 4 or 5 miles above Hancock, Md." The shale and the mode of preservation of the fossils here are as at Otisville. The material contains some recognizable parts of the integument; two carapaces, some tergites, small patches with ornamentation, and a telson. All these, save the carapaces, have the characteristics of a Pterygotus, especially in the sculpture which consists of large, semicircular, posteriorly rising scales and the telson. The smaller of the two carapaces is either a distorted Dolichopterus comparable to D. otisius, or a Pterygotus, approaching a Slimonia in outline. The larger is too incomplete for determination; what there is of it also points to the Hughmilleria-Pterygotus group. There is also a small fragment that suggests a badly crumpled carapace of Hughmilleria. On account of the interest attaching to this new locality, we have figured the carapaces and telson [pl. 70, fig. 6–8].
The third lot consists of thin slabs of waterlime, collected, according to the label, from the upper part of the McKenzie formation. In this the remains of the integument are so comminuted, that but a small tergite and several pieces with Pterygotus sculpture are recognizable.
It appears from these small lots of fossils that the peculiar eurypterid facies, both of the waterlime and of the shale extended in Cayugan time into the narrow bay reaching southward from New York into the Appalachian basin. Favorable conditions, such as for a time existed at Otisville through extensive quarrying, will undoubtedly some day bring these faunas more fully to light.
