552 CRUSTACEA. 



first joint rather longer than the second and third; the hand is hardly 

 as long as the fourth and fifth. The smaller hand is oblong, smooth, 

 with terete fingers. Some long pubescence on the third and fourth 

 pairs of legs. 



b. Orbitee margo spinula denteve armatus rostro vix breviore. 



Alpheus TRIDENTULATTJS. 



Rostrum perbreve, dentiforme. Squama antennarum externarum basalis 

 basi brevior, basi internarum vix brevior, spina externarum basalis 

 mediocris, spina internarum longissima, articido lmo multo longior ; 

 articidus 2dus lmo non longior. Pedes antici valde inceqid, manu 

 majore loevi, paulo compressd, marginibus lat£ rotundatd, digitis per- 

 brevibus, manu triplo brevior ibus. Pedes 2di Mis paulo longior es, 

 articulo carpi lmo quadruple longior e quam 2dus, 2doperbrevi, vix 

 longiore quam Stius. Articulus pedum otiorum 4ttorumve ?>tius apice 

 interfto inermis. 



Beak very short, dentiform. Basal scale of outer antennas shorter 

 than base, as long as base of inner pair ; basal spine of outer pair 

 of moderate length; of inner very long (much longer than first 

 joint), second joint of this pair not longer than first joint. Ante- 

 rior feet very unequal, larger hand smooth, but little compressed, 

 margins broadly rounded, fingers very short (not one-third as long 

 as hand) . Feet of second pair but little longer than third, first 

 joint of carpus full four times as long as second, second, third, 

 fourth all very short and nearly equal. Third joint of feet of third 

 or fourth pair unarmed at inner apex. 



Plate 35, fig. 4 a, front, enlarged four diameters ; b, part of outer 

 maxillipeds; c, larger hand, enlarged two diameters; d, smaller, ibid.: 

 e, part of leg of third pair, ibid. 



Rio Janeiro ? 



Length of body, ten lines. The three teeth of the front are very 

 low and equal. The basal spine of the inner antennaa is two-thirds as 



