3 66 



its posterior margin with 7 spines, the propodus 1,4-times as long as the carpus, dactylus one- 

 fourth of the propodus. 



Merus of fourth legs unarmed, as in A. Arethusa, 4,4-times as long as broad in the 

 middle, carpus 2,8-times as long as thick, unarmed, almost half as long as the merus, propodus 

 just one and a half as long as the carpus, with 6 spines on the posterior margin, dactylus 

 one-fourth the length of the propodus, simple. 



The only collected specimen, probably a young female, is 8 mm. long. 



f25. Alpheus pachychirus Stimps. 



Alp heus pachychirus W. Stimpson, Proc. Acad. Nat. Scienc. Philadelphia, 1860, p. 30. 

 Alpheus pachychirus J. G. de Man, in: Notes from the Leyden Museum, XII, 1890, p. 116, 



PI. 6, fig. 14 and in: Abhandl. Senckenb. Naturf. Gesell. XXV, 1902, p. 875. 

 Alpheus pachychirus A. Ortmann, in: Zoolog. Jahrb. V. Abth. f. Syst. 1890, p. 489, Taf. XXXVI, 



fig. \ja, k. 



Stat. 99. June 28/29/30. 6°7'.5 N., I20°26'E. Anchorage off North-Ubian. 16 — 23 m. Litho- 

 thamnion. 1 egg-bearing female without large cheliped. 



Stat. 133. July 25/27. Anchorage off Lirung, Salibabu-island. Reef. 1 egg-bearing female. 



Stat. 315. February 17/1S. Anchorage East of Sailus Besar, Paternoster-islands. Depth up to 

 36 m. Coral and Lithothamnion. 1 male. 



Some remarks about the collected specimens will be, 110 doubt, useful, because this 

 species is closely related to A. clypeatus Cout. 



The male from the Paternoster-islands is still young, 12,5111111. long, for this species 

 attains the length of 25 mm. There is an obtuse, median carina between the eyes, beyond 

 which it does not reach; this carina is obliquely directed downward and, curving quite anteriorly 

 suddenly downward, ends in a minute, triangular rostrum, which is 0,066 mm. long and hardly 

 broader at its base; the length of the rostrum is only one-sixth the length of i 5t antennular 

 article, as far as it is visible from above. The slightly concave, anterior margin of the front 

 curves laterally to the lateral margins. 



The 2 nd joint of the antennular peduncle is one and a half as long as the visible part 

 of the i st and twice as long as broad, while the 3 rd joint is as long as the i st . The stylocerite, 

 that reaches to the end of i st article, terminates, about as in the figure 50 of PI. LXXXVI 

 of Coutière's paper on the Alpheidae of the Maldive and Laccadive Archipelagoes, 1905, in 

 a slender spine which is half as long as the basal part. The antennal peduncle extends beyond 

 that of the upper antennae by half the length of the 3 vd article; the terminal spine of the 

 scaphocerite extends almost to the end of the antennular peduncle and reaches with one- 

 fourth of its length beyond the blade that extends almost to the middle of 3 rd article. There 

 is a v e r y s m a 1 1 spine on the anterior margin of the lower face of the basicerite ; this spine 

 is 0,14 mm. long, only twice as long as the minute rostrum. 



According to Coutière the endopod of the caudal fan should be quite unarmed; in this 

 specimen, however, one observes on its free margin 6 spines that increase in length from the 

 first to the sixth, the sixth being 0,2 mm. long, twice as long as the first. Terminal joint of 

 external maxillipeds 1,06 mm. long and 0,4 broad, 2,5-times as long as broad; the extremity 



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