365 



though obtuse process, that is curved forward; pleura of the following somites rounded. Posterior 

 margin of ó th somite with a large, acute tooth at the outer angles, but, differently from A. Arcthusa, 

 unarmed in the tniddle. Telson long 1,25 mm., 3,5-times as long as the posterior margin is 

 broad, greatest width almost twice as broad as the posterior margin, the proportion being as 

 17:9. Posterior margin not at all prominent, internal spines near the outer angles one-third 

 the width of the margin, external spines half as long as the internal ; spinules of the upper 

 surface 0,15111111. long, anterior pair twice as far distant from the posterior margin as from 

 the anterior, posterior pair almost one and a half as far distant from the posterior margin as 

 from the anterior pair. 



Second joint of antennular peduncle almost twice as long as thick, almost one and a 

 halt as long as the visible part of the i st article, which visible part appears a little longer 

 than the 3 rd ; stylocerite acute, reaching to the distal third or fourth of the visible part of 

 i st article. 



Basicerite umarmed. Carpocerite slender, projecting bevond the tip of the antennular 

 peduncle almost by the length of the terminal article-, the scaphocerite, the outer margin of which 

 is slightly concave, reaches to midway the tips of both peduncles, the blade, however, is still 

 shorter than in A. styliceps, for it only extends to the 2 nd third part of 2 nd antennular article. 



Penultimate joint of external maxillipeds one and a half as long as broad, in a lateral 

 view, terminal joint twice as long as the penultimate and four times as long as broad. 



Merus of the large cheliped stout, twice as long as broad in the middle, upper margin 

 unarmed, infero-internal margin with a rather strong, acute tooth at the far end. Large chela 

 resembling that of A. Aretliusa, a little more than one and a half as long (5,25 mm.) as the 

 carapace (3,2 mm.), rostrum included, ovoid, almost 2,5-times as long as high (2,2 mm.) and 

 almost as thick (1,9 mm.) as high; length of the fingers, i. e. the length of the dactylus 

 (1,55 mm.), not yet one-third the total length. Palm smooth, glabrous, outer face of the immobile 

 finger slightly concave, inner face convex, fingers as in A. Ar et Int sa. 



Merus of the small cheliped 2,6-times as long as wide, presenting its greatest width at 

 the anterior third, infero-internal margin with a rudimentary tooth at the far end. The chela, 

 closely resembling that of A. styliceps, is 2,3 mm. long, hardly three-fourths the length of the 

 carapace-, the length of the palm, which is one and a half as long as high and slightly 

 thicker than high, is in proportion to the length of the fingers as 10 : 13. Palm smooth 

 and glabrous, fingers shutting close together, distinctly curved inward. 



Merus of second legs 7-times as long as broad. Carpal segments 0,5 mm., 0,72 mm., 

 0,2 mm., 0,2 mm. and 0,36 mm. long, chela 0,74 mm. long (palm 0,3 mm., fingers 0,44111111.); 

 2 nd segment 4-times as long as broad, 3 rd and 4 th segments almost quadrate, their length 

 being in proportion to the width as 10 : 9. The 2 nd segment appears, like in A. Arctliusa, 

 one and a half as long- as the i st . 



Third legs resembling those of A. Arethusa, but there are 110 spinules on the posterior 

 margin of the carpus and the dactylus is sim pi e, without an accessory claw. Merus 4,1 -times 

 as long as broad in the middle, armed with a strong apical tooth, carpus almost half as long 

 as the merus, 2,8-times as long as thick, propodus 4, 4-times as long as broad, narrowing distally, 



233 



SIBOGA-EXPEDITIE XXXIX a '. 47 



