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merus; first segment 0,57 mm. long and 3,6-times as long as thick at distal extremity; following 

 segments respectively 0,14 mm., 0,13 mm. and 0,28 mm. long; chela 0,6 mm. long, compa- 

 ratively shorter than in the adult, being but a little more than twice as long as the fourth 

 segment ; fingers slightly shorter than the palm. 



Relative dimensions of third legs: merus 2, resp. 1,9; carpus i; propodus 1,9, resp. 1,8. 

 Merus 4,65-, resp. 4,7-times as long as wide, propodus 7-, resp. 6,8-times, the latter with 10 

 very short spinules and a somewhat longer one at the distal extremity ; the short spinules are 

 0,056 — 0,07 mm. long. Dactylus a little more than one-fourth of the propodus. 



f 2. Arete dor sal is Stimps. 



Arete dorsalis W. Stimpson, in: Proc. Acad. Nat. Scienc. Philadelphia, i860, p. 32. 

 } Arete dorsalis Pacificus H. Coutiere, in: Bull. Soc. Philom. Paris 9. V, 1903, p. 17. 

 } Arete dorsalis H. Coutiere, Alpheidae Maid, and Laccad. Archip. 1905, p. 866, Fig. 136, 137. 



Nee: Arete dorsalis J. G. de Man, in: Archiv f. Naturgeschichte. 53. Jahrg. 1888, p. 527. 



Stat. 78. June 10,11. Lumu-Lumu-shoal, Borneo-bank. Reef, i adult egg-bearing female. 

 Stat. 213. September 26 — October 26. Pulu Pasi Tanette. Reef, i ova-bearing female. 



These two specimens, in either of which the legs of the first pair are unfortunately 

 missing, do not quite accord with one another : the slight differences are perhaps due to the 

 difference of age, for the adult female from Stat. 78 is 16 mm. long, the other only 9,5 mm. 

 Perhaps, however, these specimens may once prove to belong to different species. They show 

 also differences from Coutiere's description and figures, so that I am not quite sure whether 

 both specimens in reality appertain to the form described by that author. 



In a lateral view the carapace of the female from Stat. 78 appears hunch-backed, 

 the upper border being arcuate and the rostrum strongly bent downward. Looked at from 

 above the acute rostrum that reaches almost to the end of the second antennular article, 

 much resembles the figure 136 of Coutiere's paper, but the lateral margins regularly curve into 

 the upper orbital margins, whereas in that figure they make a right angle with one another; 

 looked at from above, the rostrum appears to be about one-third longer than wide at its base, 

 the width at the base could not be measured exactly, because there are no angles. In a 

 lateral view the spine at the outer angles of the orbits (epine extra-corneenne of Coutiere) 

 hardly reaches to the middle of the eyes. 



According to Professor Coutiere the length of the telson should be 3,5-times the width 

 of the posterior margin, in both specimens this proportion is indicated by a larger number, the 

 proportion being 4,42 in the female from Stat. 78 and 4,2 in the other specimen. Posterior 

 margin not much prominent, outer angles acute, very short ; the inner longer spinules are 

 hardly longer than the spinules of the upper surface and project by half their length beyond 

 the posterior margin. The spinules of the upper surface are small, 0,1 mm. long, V.^j of the 

 length of the telson ; they are implanted close to the lateral margins on the distal half and 

 the posterior pair is one and a half as far distant from the posterior margin as from the 

 anterior pair. 



In the female from Stat. 78 the third antennular article is nearly one and a half as 



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