. Decapod crustaceans of the northwest coast of North America ... Crustacea -- North America. DECAPODS 8i SPIRONTOCARIS TRIDENS Rathbun. Spirontocaris tridens Rathbun, Proc. U. S. Nat. Mus., xxiv, 896, 1902. Allied to S. gracilis, S. flexa, and S. decora^ but more robust than these. Female.—The median crest occupies the anterior third of the carapace; superior spines or teeth 3, one on the carapace, one (the largest and highest) over the base of the eye-stalk and nearer to the anterior than to the posterior tooth. In front of the teeth the rostrum has al- most no upper limb and is gently ascen
. Decapod crustaceans of the northwest coast of North America ... Crustacea -- North America. DECAPODS 8i SPIRONTOCARIS TRIDENS Rathbun. Spirontocaris tridens Rathbun, Proc. U. S. Nat. Mus., xxiv, 896, 1902. Allied to S. gracilis, S. flexa, and S. decora^ but more robust than these. Female.—The median crest occupies the anterior third of the carapace; superior spines or teeth 3, one on the carapace, one (the largest and highest) over the base of the eye-stalk and nearer to the anterior than to the posterior tooth. In front of the teeth the rostrum has al- most no upper limb and is gently ascending and slightly curved ; midrib rather stout and acute at tip; the lower limb diminishes ante- riorly and is armed. Fig. 34. Spironiocaris tridcns. 9 . Station 2865. a. Side of carapace and abdomen (X ij)- b. Dorsal view of anterior portion (X 3)- with 3 to 6 teeth, one near the tip. Rostrum longer than the carapace or antennal scale. Anterior margin of carapace furnished with a strong antennal and a very small pterygostomian spine. Antennular peduncle extending two fifths the length of the antennal scale; second and third segments short and subequal; basal scale with a spine which extends nearly to the end of the second segment. The thickened portion of the outer flagellum reaches nearly to the end of the antennal scale; inner flagellum twice as long. The antennal pedun- cle extends a little beyond the end of the second antennular segment; the flagellum is nearly as long as the body; the scale, measured along its outer margin, is a little shorter than the carapace. The maxillipeds reach two thirds the length of the antennal scale; the first pair of feet barely to the end of the antennal peduncle. The tip of the second pair when extended hes between the end of the maxilhped and that of the antennal scale; the tip of the last pair lies between the end of the maxilliped and the antennal peduncle. The abdomen has the third segment well produced backward, and its posterior port
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