Macrochirus group. 



a x Merus of 3 rd and 4 th legs with an acute tooth at the distal extremity 



of posterior margin. 



<$] Lateral (extra-corneal) teeth present, very small. Between either of 



them and the rostrum the frontal margin bears another still smaller 



tooth. An acute median tooth on the rostral carina at the base of 



the eye-hoods. Carapace villose villosus (Oliv.) 



(H. Milne-Edwards, in: Hist. Nat. Crust. II, 1837, p. 354). 



b„ Lateral (extra-corneal) teeth wanting. 



£, Dactyli of three posterior legs biunguiculate. Lower spine of basi- 

 cerite reaching almost to the extremity of median article. Lower 

 border of the large chela notchecl, upper border without a trans- 

 verse groove. First carpal article of 2 lld legs more than twice 

 as long as 2 nd paragracilis Cout. 



(H. COUTIÈRE, Alpheidae Mald. and Laccad. Archip. 1905, p. 883, PI. LXXVI, 

 fig. 22). 



c„ Dactyli of three posterior legs simple. Basicerite almost unarmed. 



Lower border of larger chela entire, upper border with a transverse 



groove. First carpal article of 2 nd legs about one-third of 2 lld . 



d } Longitudinal groove on the supero-external surface of larger chela 



well-developed, deep. Fingers of the small chela much shorter 



than the palm aatto-femorafusDana. 



d„ Longitudinal groove on the supero-external surface of larger chela 



very feeble. Fingers of the small chela as long as the palm. Amirantei Cout. 

 (H. COUTIÈRE, in: Buil. Soc. Philom. Paris, 1908, p. 15). 

 a„ Merus of 3 rd and 4 th legs unarmed. 

 b x Lateral (extra-corneal) teeth present. 



c ï Dactyli of three posterior legs biunguiculate. 



d x Inferior spine of basicerite small, hardly reaching to the extremity 

 of i st antennular article. 

 6', Larger chela not emarginate anteriorly, dactylus not hammer- 

 shaped. Scale of scaphocerite not rudimentary, reaching to 

 or almost to the extremity of antennular peduncle. 

 ƒ, Larger chela not or quite indistinctly notched at the base of 

 the immobile fingfer. Rostrum reachinsr to the middle of 

 the visible part of i st antennular article. Movable spine of 

 exopod of caudal fan brown. First carpal article of 2 nd legs 

 only slightly longer than the sum of the 2 nd and the 3 rd . gracilis Heller 



(C. Heller, in: Sitzungsber. Akad. Wiss. Wien, XLIV, 1861, p. 271, Taf. III, 

 Fig. 19, 20). 



178 



