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m.^ Rostrum narrow, obtuse, subulate. Lobes terminating 

 the upper and the lower margin of larger chela 



acute cliiragj'icus H.M.Edw. 



/„ Smaller chela of the male less than 4-times as long 

 as high, with both margins distinctly notched; lobes 

 terminating both margins of larger chela obtuse, 



rounded crassiiiianus Heller ^) 



k^ Merus of 3''^ legs more than 6-times as long as wide ; 



rarely 5, 4-times, but in this case the lower border 



of the larger chela hardly emarginate. 



/j Smaller chela of the male of a rather stout form, the 



proportion between length and height being 4 or less, 



with an acute tooth at either side of the articulation 



of the dactylus. 



Wj Merus of 3''^ legs in adult specimens somewhat more 



than 6-times, in younger individuals almost 7-times 



as long as wide, with the extremity of the lower 



margin rather sharp parenchirus Cout. 



Wj Merus of 3'''^ legs 5, 4-times as long as wide, with 

 the extremity of the lower margin rounded 



pareuchirtis Cout. var. Leruothca de Man 



/g Smaller chela of the male at least 5-times as long as high, 

 carpocerite just as long as the antennular peduncle. 

 Merus of 3''i legs 7, 5 -times as long as wide. 

 111^ Frontal margin distinctly emarginate near the base 

 of the rostrum ; 2"^^ antennular article a little longer 

 than the visible part of the i^'; larger chela 

 distinctly emarginate on the lower margin. . . leptochiriis Cout. 

 (H. CoUTIERE, Alpheidae Maid, and Laccad. Archip. 1905, p. 914, PI. LXXXVII, 

 fig- 54)- 



-Wj Frontal margin straight near the base of the rostrum ; 

 2^'^ antennular article a little shorter than the visible 

 part of the i^'; larger chela with the lower margin 

 only slightly sinuous leptochiroides de Man 



l) It remains uncertain whether tlie Japanese A. lobidens de Haan is identical with A. crassima/iits or not. I was unable to 

 examine the single type specimen of A. lobidens^ that is still preserved in the Leyden Museum, but that, as Dr. Horst informs me, 

 is broken and fragmentary. I was, however, enabled to study two specimens of the species referred by Dr. Ortmann to A. lobidens 

 (in; Zool. Jahrb. V. Syst. 1890, p. 474, Tab. 36, fig. 13); unfortunately these specimens which 1 received from the Museum at Strassburg, 

 were desiccated and in a bad state. They bpre a close resemblance to A. crassiniamts^ especially the legs of the P' pair, but those of 

 the 2"'' were somewhat different. The merus of the 2"d legs pi-oved to be 8, 5-times longer than wide and the carpal segments were 

 1,8 mm.; 1,8 mm.; 0,52 mm.; 0,48 mm. and 0,7 mm. long, the I*' segment 5, 6-times longer than thick at distal extremity. These legs 

 appeared therefore a little more slender than those of A. crassimanus and the 2"^ segment was just as long as the i". The question 

 whether both species are different or not, must be left to further researches. 



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