231 



A new form of the Xeomeris group, closely related to Syn. streptodactyhis Cout. 



In Sy7t. neomeris (de Man), Syn. streptodactyhis Cout., Syn. Gravieri Cout. and still other 

 species the rostrum is separated posteriorly from the supraorbital spines by the concave, anterior 

 wall of the front, the anterior margin of which is distinctly visible at either side beneath the 

 rostrum, when the carapace is looked at from above. In this new species the rostrum is 

 comparatively broader than in Syn. streptodactyhis, being 2,2-times as long as broad at its 

 base, in Syn. streptodactyhis 2,75 — 3,25, usually 3-times; it extends to the distal sixth of the 

 visible part of first antennular article and the tip is hardly turned upward; the supraorbital 

 spines, distinctly shorter than the rostrum and hardly reaching beyond the middle of the first 

 article, are slightly directed downward and make acute angles with the rostrum, at least the 

 left spine, for the right is much shorter and apparently mutilated, while the anterior wall 

 of the front is not visible at all; the acute tip of the supraorbital spines is glabrous, like the 

 rostrum, and very slightly turned outward. 



Second antennular article a little more than two-thirds as long as the first and almost 

 one and a half as long as thick; stylocerite reaching to the 2"'* fourth or fifth of median article. 

 The carpocerite extends by two-thirds the length of the third article beyond the tip of the 

 antennular peduncle; terminal spine of scaphocerite hardly longer than the antennular peduncle, 

 distinctly shorter than the carpocerite; blade reaching the middle of third antennular article, 

 lower spine of basicerite as long as the stylocerite and projecting straight forward, upper spine 

 small, measuring, in a lateral aspect, one-fourth of the lower. 



Telson 2, 5 3-times as long as the posterior margin is broad, the latter as in Syn. strepto- 

 dactyhis^ with the outer angles acute, though not prominent; greatest width twice as lono- as 

 the posterior margin. Spinules of upper surface 0,07 — 0,08mm. long, much smaller than 

 those of Syn. streptodactylns and situated close to the lateral margins; while in Syn. strepto- 

 dactyhis the anterior pair is always situated before the middle, it is in this species situated 

 posterior to the middle, the proportion between the length of the telson and the distance 

 of the anterior pair from the posterior margin being 2,19. The proportion between the distances 

 of the two pairs from the posterior margin is indicated by the number 1,7. 



In both chelipeds the upper margin of the brachium ends in a minute, acute tooth ; 

 fingers of the large chela a little longer than those of Syn. streptodactyhis. Small chela as in 

 this species, fingers i mm. long, total length 2,3 mm., height 0,76 mm., proportion between the 

 total length and the height 3, proportion between the length and the height of the palm 1,71. 



First segment of the carpus stout, 4-times as long at thick distally, slightly shorter 

 than the followino- segments taken together. 



The relative measurements of the third legs are: carpus i; merus 2,44; propodus 2,1 2 v 

 The merus, just as long as the carpus of the second legs, is 3,68-times as long as wide and 

 bears, a little beyond the middle, a single spinule long 0,09 mm. The carpus, measured from 

 articulation to articulation, appears to be 2,5-times longer than wide and presents a more 

 slender form than in Syn. streptodactyhis. The propodus is 5,66-times longer than wide, with 

 8 spinules long 0,09 — 0,1 mm. on the posterior margin, besides those at the distal extremity. 

 Dactj'lus (0,39 mm.) half as long as the carpus and almost one-fourth of the propodus (1,7 mm.), 



99 



