Discovery reports (1941) Discovery reports discoveryreports20inst Year: 1941 LARVAE OF SERGESTES 31 specimen observed represented by a pair of minute spines. Two pairs of lateral spines retained. Hepatic and posterior dorsal spines present, small. Abdominal somites with small dorsal spines, that of somite i minute. Lateral spines of same form as in Acanthosoma, but reduced in length. Telson very little changed from Acanthosoma, 2J times as long as wide, with long lateral spines; apical fork slender, the arms parallel, with two outer and three inner spines. Antennal scale as in Acantho- soma,
Discovery reports (1941) Discovery reports discoveryreports20inst Year: 1941 LARVAE OF SERGESTES 31 specimen observed represented by a pair of minute spines. Two pairs of lateral spines retained. Hepatic and posterior dorsal spines present, small. Abdominal somites with small dorsal spines, that of somite i minute. Lateral spines of same form as in Acanthosoma, but reduced in length. Telson very little changed from Acanthosoma, 2J times as long as wide, with long lateral spines; apical fork slender, the arms parallel, with two outer and three inner spines. Antennal scale as in Acantho- soma, widening towards end, with very long apical spine; flagellum shorter than body. Fig. 23. S. robustiis. a, Mastigopus i; b, Mastigopus 2; c, telson; d, telson, stage i. Eye about one-sixth length of body, with small, nearly round, eyeball, and no anterior papilla. Labral spine absent. Mandible without palp. Legs with small vestiges of exopods. Pleopods very long; i and 2 without endopods; 3-5 with very small rudiments of endopods. Uropods nearly seven times as long as wide (67 : i), the large outer spine in middle of margin. In stage 2 (Fig. 23 b, c) the carapace has lost its dorsal and lateral spines, and the dorsal spines on abdominal somites 1-3, but the antennal flagellum is still short. The development of the telson is shown in Fig. 24. The youngest stage figured by Hansen (7-6 mm.) is probably stage 2, since he does not mention the vestigial exopods on the legs; also the lateral spines on the abdomen
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