158 



is wide, the anterior pair twice as far distant from the end of the telson as from the base, 

 posterior pair nearly midway between the anterior pair and the posterior margin. 



Merus of second legs very slender, 12-times as long as thick. Carpus 1,17-times as 

 long as the merus ; the first segment, 8-times as long as thick, appears a little longer than 

 the sum of the four following, the proportion being as 1 : 0,8, and it is 0,61 mm. long; the 

 following segments are 0,09 mm., 0,1 mm., 0,1 mm. and 0,2 mm. long. The second segment 

 is just as thick as long, the two following almost as thick as long, the fifth twice as long as 

 thick. Chela twice as long as the fifth segment, 3,5-times as long as broad and the fingers are 

 one and a half as long as the palm. 



The three posterior legs are very slender, thin, glabrous and unarmed, 

 excepting the ischium of the 3 rd and of the 4 th pair that bears two spines, one near the base, 

 the other in the middle. Measurements of the 3 ld pair: merus 1,6; carpus i; propodus 1,53; 

 merus 9-times, carpus 7-times as long as thick; propodus without spinules, 14-times as long as 

 wide. Dactylus simple, tapering, slightly curved, measuring two-fifths of the propodus and 

 10-times as long as thick at its base. The ischium of the fifth pair is probably unarmed. 

 Measurements of these legs: merus 1,4; carpus i; propodus 1,57. Merus 11-times, propodus 

 1 4-times as long as broad in the middle ; carpus 8-times as long as thick distally. Dactylus 

 three-fifths of the propodus, slightly curved, simple, tapering, 13-times as long as thick at 

 the base. A few short setae at the far end of the propodus. 



This specimen, which is probably young, is 7,3 mm. long, the carapace, rostrum included, 

 2,8 mm.; the rostrum measures hardly more than one-fifth the length of the carapace. 



Jousseaumea Cout. 



Also this genus comprises only a few species. Three species namely : Jous. serratidigitus 

 Cout., Jous. latirostris Cout. and Jous. cristata Cout., occur at Djibouti, in the Gulf of Aden, 

 a fourth, Jous. Ortmanni Cout., inhabits the coast of America and the fifth, Jous. trigona 

 Rathb., occurs at the shores of the island of Porto Rico. Two species, referred to this genus 

 and both new to science, were collected by the "Siboga": Jous. Sibogae de Man, taken near 

 South-Lucipara-island in the Banda Sea and Jous. hilarula de Man from the Sea between 

 Misool and Salawatti. These two species differ from the three that occur on the reefs of 

 Djibouti, at once by the posterior margin of the telson being marked with a median, trapezi- 

 form notch, at either side of which only two spinules are implanted instead of four. 



f 1. Jousseaumea Sibogae de Man. 



J. G. DE Man, in: Tijdschr. d. Ned. Dierk. Vereen. (2) Dl. XI, 19 10, p. 303. 

 Stat. 225 c . November 8. South of Lucipara-islands. Reef. 1 female with eggs. 



Rostrum triangular, one-fourth longer than wide at its base, acuminate, with the lateral 

 margins slightly concave and extending a little beyond the middle of third antennular article ; 

 upper surface slightly convex, not carinate, in a lateral view it appears narrow or low, slightly 

 directed downward, with the lower margin straight and the upper arcuate. Extra-corneal 



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