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Show 758 MR. W. F. LANCHEBTER ON CRUSTACEANS [June 19, are representative of the species : and two males and two females (although with some doubt) of M. Zehntner's variety. I also find two males answering to Dr. de Man's var. crassimana ; these were obtained on the shore. Dim. d 14x13. $ 17x15. Var. crassimana. d H'5 X 10*25. d 7'75 x 7'25. Var. Icevimana? d 12x10-5. d 12-75x11. $ 10x9. $ 9x7-75. 87. SESARMA FASCIATA, sp. nov. (Plate XLVII. fig. 12.) Hab. Singapore: marshy ground near sea. One male and three females. This species belongs to Dr. de Man's subgenus Parasesarma, in which the sides have no tooth behind the orbital angle, and in which there are two or more pectinated ridges on the palms. Carapace smooth to the eye, but under the lens seen to be closely punctated everywhere : sides nearly parallel (but broken up in one of the females just behind the eyes so as to give indications of a tooth behind the orbital angle). Tooth at distal end of the upper border of the merus very small and obtuse, and the anterior border only slightly expanded, the long proximal edge of the expansion being dentated. External surfaces of merus and carpus rugose, inner angle of carpus with a large triangular tooth; outer surface of palm and fingers quite smooth to the eyes, but minutely punctate under the lens ; whole inner surface of chelipedes smooth. Inner upper border of hand thick and prominent: external to this there are three pectinated ridges, which lie more nearly longitudinal than transverse. The middle one consists of:-a, a short distal portion, practically one with the distal part of tbe inner upper border; b, a longer middle portion running obliquely from near the upper border to the upper part of the posterior border, and cutting off a small semicircular piece of the upper surface in which lies another very small pectinated ridge ; and c, a proximal portion, curving sharply from the middle portion to run parallel to the posterior border as far as the joint of hand and carpus. The third pectinated ridge starts from the inner and upper base of the dactyl, to run in front of, and parallel with the middle portion of the middle ridge, and to stop abruptly half-way between its starting point and the joint of band and carpus. Only 5 or 6 obscure, low tubercles can be distinguished on the upper margin of the dactyl, which stop some distance from the tip: inner margins of both fingers with 4 or 5 broad triangular denticulations. Meri of ambulatory legs with a subdistal low and blunt spine; remaining joints with hairs, rather diffuse, but tending to be arranged on the anterior and posterior margins. Male abdomen seven-jointed, broad, regularly tapering from the middle of the 3rd segment to the middle of the 6th where it suddenly narrows ; the 7th has a rounded extremity, parallel sides, and is only a little longer than broad. Colour a deep crimson red, with regular mottlings of a light yellow, and a light yellow band, or faacia, placed transversely on the frontal |