102 CRUSTACEANS OP THE 



cely so. With regard to the rugosities on the subhepatic 

 and subbranchial regions both species nearly resemble one 

 another, they are, however, less prominent. The epistome 

 presents also the same characters, but the lobe at the ante- 

 rior extremity of the lateral margins of the buccal frame, 

 that in Pot. sinuatifrons is crenulate, appears nearly smooth, 

 just as in Fot. mahakkamense. The external maxillipedes 

 fully agree in both species. Sternum and abdomen are 

 smooth, finely punctate. 



Though the type-specimens of Pot. sinuatijrons are all 

 males, the anterior legs seem to resemble those of the 

 female from the Upper Sibau. The left is a little larger 

 than the right. The angles of the lower surface of the 

 arms are distinctly granulate in Pot. sinuatifrons, but almost 

 smooth in the female, the rugosities on the upper edge are 

 also less defined. The upper surface of the wrists carries 

 very small , partly inosculating grooves and depressions , 

 but in the males of Pot. sinuatifrons one observes finely 

 granulated raised lines ; just as in this species the inner 

 augle is armed with a short conical spine, beneath which 

 is a very small one. The chela of the left leg is just as 

 long as measures the distance between the outer orbital 

 angles, the fingers, in contact throughout their length, 

 are a little longer than the palm, that is somewhat less 

 high at the articulation of the fingers than it is long. The 

 outer surface of the palm is beset with transverse rugo- 

 sities and inosculating foveae , but in the types of Pot. 

 sinuatifrons transverse granulated lines are seen at least 

 on the upper margin and on the upper half of the outer 

 surface and some granules at the base of the index. The 

 fingers are distinctly grooved and multidentate. The ambu- 

 latory legs resemble those of Pot. sinuatifrons, but the 

 propodites of the 5^^ pair are slightly broader and the 

 dactylopodites a little shorter and stouter. 



The male from Mount Damoes differs from the female 

 by the following. The cephalothorax isalittle broader 

 anteriorly, as is proved by the proportion between its length 



iNotes from tlie Leyclen Museum, Vol. XXI. 



