Pterygotus (Erettopterus) globiceps nov. Page 374

• 1 Nepionic stage showing the enormous size of the lateral eyes, the position of the ocelli and the small number of segments. × 30
• 2 Another larval specimen showing slightly different form of carapace, thickened rim of eyes and small number of segments of tapering abdomen. × 30
• 3 An older (neanic) stage in which the abdomen has assumed the proportion and composition of the adult stage. A broad thickened rim surrounds the eyes. × 12
• 4 Carapace of a young individual showing somewhat different characters, apparently due to compression in longitudinal direction. × 15
• 5 Fragment of carapace of young individual, showing the smooth cornea of the eyes partly separated from the facettae. × 5
• 6 Well preserved carapace. Type of the species. × 3
• 7 Largest carapace observed. Shows the lateral eye, somewhat distorted by oblique compression (indicated by the wrinkles) and the ocelli. On the antelateral corner a fragment of the marginal shield of the ventral side with traces of ornamentation is seen. Natural size
• 8 Tergite showing antero-lateral lobes and ornamentation. × 3
• 9 Second sternite with genital appendage of young female. × 3
• 10 Swimming leg. Natural size

Pterygotus (Erettopterus) sp.

• 11 Portion of a telson showing fine bristles on the margin. Natural size
• 12 Telson of young individual. × 3

The figures 8, 10, 11 are referred with doubt to this species.

Pterygotus? sp. 13 Problematical fossil, possibly the female genital appendage of a Pterygotus [cf. similar appendage of Pterygotus anglicus, Huxley and Salter, pl. 3, fig. 4, 5, 7]. Horizon and locality. Shawangunk grit. Otisville, N. Y.

The originals are the State Museum