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I cannot say to which group the fourth new species, Ath. tenuipcs, ought to be referred, 

 because the chelipeds are missing. This species, observed at the entrance of Kwandang-bay, 

 may, however, easily be distinguished by the very slender legs of the second to fifth pairs. 



Key to the species of the genus Athanas. 



a x Legs of the first pair with the carpi and the chelae directed straight 



forward, merus short. [Nitescens group). 



ö 1 Dactyli of three posterior legs simple. Supra-corneal spine more or 



less developed. 



c 1 Supra-corneal spine little marked, a more or less obtuse prominence. 



Infra-corneal spine distinctly developed. Carpus of the first pair 



of legs, in the female, about twice as long as thick at the 



distal extremity, merus measuring two-thirds the length of the 



chela nitescens Leach (veloculus Sp. Bate) 



(Vide: C. HELLER, Die Crustaceen des südlichen Europa. Wien 1863, p. 281, 

 Taf. IX, Fig. 21—23 and C. Spence Bate, Report Challenger Macrura, 1888, 

 p. 529, PI. XCVI, Fig. 1). 



c„ Supra-corneal spine quite conspicuous, prominent. Carpus of the first 

 pair of legs, in the female, one and a half as long as thick at the 

 distal extremity, merus measuring two-thirds the length of the chela. 



d x Infra-corneal spine distinctly developed Naifaroensis Cout. 



(H. COUTIÈRE, Alpheidae Mald. and Laccad. Archip. 1905, p. 859, Fig. 131). 



d a Infra-corneal spine wanting areteformis Cout. 



(H. COUTIÈRE, Alpheidae Mald. and Laccad. Archip. 1905, p. 860, Fig. 132). 

 b„ Dactyli of three posterior legs with a small, ventral, accessory tooth, 

 acute and conical, that makes 110 angle with the posterior margin 

 of the dactylus. Legs of the first pair of equal shape in the male 

 and in the female; carpus, in the female, even a little shorter 

 than thick at the distal extremity, merus half as long as the chela. 

 Appendix masculina elongate, reaching beyond the tip of the inner 

 ramus of 2 nd pleopods and inserted on the middle of the ramus. Grimaldii Cout. 1 ) 



(H. COUTIÈRE, in: Buil. de 1'Institut Océanogr. Monaco. N° 197. — 20 Janvier 191 1). 



1) In Coutière's description of Ath. Grimaldii the dactyli of the three posterior legs are said to be simple, but Professor 

 Coutière wrote me afterwards the following : "Quant aux dactyles 3, 4, 5, ils possèdent évidemment une tracé de division, Ie bord libre 

 est tres légèrement interrompu, et la partie distale de la griffe est aussi plus mince que la partie proximale, comme si on 1'avait creusée 

 latéralement". Through the courtesy of Professor Lenz of the Naturhistorisches Museum at Lübeck I was able to study 8 specimens of 

 Ath. Grimaldii collected at Porto Grande, St. Vincent, Cape Verde Islands and so I could establish the fact that the dactyli terminate, 

 at the distal third of their posterior margin, in a small, acute, conical, accessory tooth, which is separated by a narrow 

 incision from the distal part of the dactylus and which makes no angle with the posterior margin, the tooth being directed toward the 

 distal extremity of the joint. Properly speaking the dactyli are therefore in reality biunguiculate, though they appear simple when 

 examined under a feeble magnifying-glass and this opinion is corroborated by the following observation. In one of the specimens, an 

 egg-bearing female, about 12 mm. long, the accessory hook of the dactyli of the 3 rJ and 5 th legs is directed backward, making a distinct 

 angle with the posterior margin, about as in Ath. Granti^ whilst in the 4'h legs it shows the normal typical form : as this specimen for 

 the rest fully agrees with the others, it must evidently be regarded as an individual variety. In this specimen the meri of the 3 rd legs 

 proved to be 3,8-times as long as wide, in another specimen, also an adult female, 4-times, and in a young specimen 3,S5-times: according 

 to the original description the proportion should be 4,6 — 4,9. 



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