Kiaeropterus or Clarkeipterus (Dolichopterus) otisius Clarke Page 270 1 Carapace showing a broad furrowed rim, the large compound eyes and the ocelli. × 3 2 Carapace showing the visual area of the compound eyes and the ocellar mound. × 3 3 Slightly smaller carapace and two tergites. The compound eyes are depressed showing the thickened rim of the ocular node. × 3 4 Carapace of young individual showing the greater prominence of the ocellar mound. × 3 5 A presumably mature, well preserved carapace, showing the normal outline, a flat border and thickened rim, the crescent-shaped visual area of the compound eyes and a depression in the ocular node. × 3 6 Interior view of a small carapace with two attached tergites. × 3 7 A fragmentary carapace of a younger individual, referred in the preliminary paper with doubt to Eurypterus myops [see pl. 6, fig. 6]. × 3 8 The type (holotype). × 1½ Horizon and locality. Shawangunk grit. Otisville, Orange co., N. Y.

The originals are in the State Museum

Ruedemannipterus (Dolichopterus) stylonuroides nov. Page 276 9 Small carapace showing the rim of the dorsal side. × 3 10 Larger carapace showing both the rim of the dorsal side and the doublure of the ventral side. Natural size 11, 12 The two counterparts of a carapace; the first showing more distinctly the rim of the upper side, the other the doublure of the under side. Natural size 13 Single specimen with tergites and swimming leg. The holotype of the species. Shows the characteristic outline and broad doublure of the carapace, the anterior position of the eyes and the lobelike appendages of the distal joints of the swimming leg, and in the narrow tergites indications of the slender form of the abdomen. × 3 14 Fragment of tergite, possibly belonging to this species. Natural size Horizon and locality. Shawangunk grit. Otisville, Orange co., N. Y.

Hughmilleria socialis Sarle 15 Epistoma, figured by Sarle as metastoma of Stylonurus? × 3½. See page 428 Horizon and locality. Pittsford shale. Pittsford, Monroe co., N. Y.

All originals are in the New York State Museum