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which are hardly longer than the palm, is 0,84 mm. long, almost as long as the first segment 

 of the carpus. According to Heller the first segment should be as long as the sum of the 

 three following, a difference probably due to the larger size of his specimens. 



Relative dimensions of the third legs : merus 2,2; carpus i; propodus 1,9. The merus, 

 3,1-times as long as wide, bears some short setae on both margins, especially on the upper 

 and a tuft of longer setae at the far end of the latter. The carpus, 2,27-times as long as thick, 

 and the propodus, 5-times as long as wide, are on their anterior border beset with rather 

 Ion o- setae and the posterior margin of the propodus bears, besides those at the distal 

 extremity, five spinules which are 0,13 — o, 16 mm. long. The dactylus, measuring somewhat less 

 than one-third of the propodus, has a rather stout form, being, from the proximal end of the 

 anterior margin to the tip of the ventral hook, twice as long as wide near the articulation. 

 The obtuse ventral hook which is as long as wide at its base, is spoon-shaped and 

 excavate and makes an acute angle with the pointed dorsal hook which is just as long but 

 hardly half as thick at its base as the other; the slightly curved, dorsal hook is grown together 

 with a process of the superior border of the dactylus to a little beyond the middle and appears 

 therefore thickened along its proximal half. 



This specimen is 12,5 mm. long. 



Remarks. This species, no doubt identical with that observed by Coutière, seems to 

 be also the species described by Heller, though, according to this author, the upper margin 

 of the three posterior legs should be quite glabrous. The species, however, which was described 

 by me (1. c. 1S97) under the name of Alp heus Charon, is apparently a different form. 

 The three frontal spines are other wise shaped and, according to Fig. 63 of my paper, also 

 the antennular peduncle, while the lateral spine of the scaphocerite is curved inward and hardly 

 exceeds the scale; the telson appears a little shorter with regard to the width of the posterior 

 margin. The third legs have a stouter form, the propodus is 4-times as long as wide and the 

 dactylus also differs; the dactylus, indeed, measures a little more than one-third the propodus 

 and is 2. 5-times as long as broad at its base, while, in my description, nothing is said about 

 the excavate appearance of the ventral hook. The two described specimens had been received 

 by me from the Museum at Vienna under the name of A. Charon Heller and had been 

 collected by the Novara-Expedition at the Nicobar Islands. We must therefore conclude that 

 Heller was mistaken when referring these specimens to the true Syn. Charon from the Red 

 Sea and that he was misled by the apparent resemblance of both species. This different species 

 may henceforth bear the name of Syn. Helleri (vide p. 194). 



General distribution: Red Sea (Heller); Maldive and Laccadive Archipelagoes 

 (Coutière); Hawaiian Islands (Coutière). 



f17. SynalpJieus Nilandensis Cout. 



Synalpheus Nilandensis H. Coutière, Alpheidae Mald. and Laccad. Archip. 1905, p. 871, 



PI. LXX, lig. 4. 

 Synalpheus Nilandensis G. Nobili, Ricerche sui Crostacei della Polinesia, Torino 1907, p. 353. 



Stat. 51. April 19. Southern part of Molo-Strait. 70 m. Fine grey sand. 2 specimens. 



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