CRUSTACEA OF THE MEKGTJI ARCHIPELAGO. 55 



tubercular eminence, as ia S. serratifrons, or a small toothy as in 

 S. austr alien sis. The basal joint of the external antenme is 

 short and small, and does not nearly reach the front ; the other 

 joints occupy the internal orbital hiatus, and the flagellum is 

 rather short, measuring only a fourth of the distance between 

 the third antero-lateral teeth. The endostome is distinctly longi- 

 tudinally ridged on each side. The epistome is nearly smooth. 

 The male abdomen is seven-jointed, the joints being all distinctly 

 separated from one another ; it closely resembles that of some 

 Pilumni, and the penultimate joint is nearly quadrate, being 

 scarcely broader than long. The sternum and the abdomen are 

 smooth, though somewhat pubescent, and the lateral margins of 

 the female abdomen are fringed with rather long hairs. 



The chelipedes are very unequal, the right being the largest 

 in both specimens ; although the larger chelipede of the female 

 specimen is wanting, I suppose that the anterior legs pre- 

 sent the same size both in the male and in the female. The 

 arms are short, scarcely projecting laterally beyond the lateral 

 margins of the cephalothorax ; they are armed near the distal 

 end of the upper margin with a strong, acute, somewhat curved 

 tooth. The under margin is entire, but the anterior margin is 

 somewhat granular and hairy. The external (or posterior) sur- 

 face of the arm is minutely granular near the upper margin, but 

 otherwise the arms appear smooth. The wrist is armed with a 

 small, scarcely acute tooth at the distal and internal angle ; its 

 upper surface appears smooth to the naked eye, but, when seen 

 under a lens, some small granules are observed near the internal 

 and external margins, especially on the Avrist of the smaller 

 chelipede. The larger hand is yery large, its length (the fingers 

 included) being but little shorter than the breadth of the 

 cephalothorax, i. e. the distance between the third antero-lateral 

 teeth. The fingers are nearly half as long as the palm, which 

 is but little longer than broad (high). The outer surface 

 of the palm is rather convex and quite smooth, and the obtuse 

 upper and under margins, like the inner surface, are also per- 

 fectly smooth. The fingers have pointed tips, which cross one 

 another ; they are nearly smooth, the immobile finger pre- 

 senting only a trace of a longitudinal impressed line on its 

 outer and inner surfaces, and the mobile finger being slightly 

 granular above at the articulation. The latter presents a some- 

 what larger tooth at its base, and the other finger is armed with 



