Boone, Crttstacea, Cruises of "Ara" and "Alva** 211 



grooves, which with the rounded ridges between combine to give 

 the surface a rippled appearance, very like the water-marks in 

 the sand. 



The chelipeds are subequal in the male with only the distal 

 portion of the merus visible dorsally, this being expanded sub- 

 distally into a quadridentate, marginal lamina that continues the 

 line of the posterior dentate margin of the clypeiform process 

 and in turn is continued anteriorly by the dentate-crenulate lower 

 margin of the propodus ; the true distal meral margin is smooth, 

 interfits at the inner distal angle into a notch on the carpal mar- 

 gin and is subdentate at the outer angle; the upper surface of 

 the carpus is smooth except for two grooves which originate near 

 the outer proximal angle, the shorter one curving transversely 

 across the proximal region and the longer one running above and 

 subparallel to the distal, outer, carpal margin. The palm is high, 

 produced on the upper margin into a dentate crest, cut into about 

 seven teeth, which increase in height from proximal to distal, 

 the distal four being quite acuminate; there are also about six 

 to eight low nodules below the distal portion of the crest and 

 along the distal margin above the base of the hinged finger. The 

 fingers are deflected and inbent. The lower margin of the palm 

 is regularly beaded and there is above this a ridge-like series 

 composed of a proximal tooth and six large, rounded nodules, 

 well spaced, which increase in size distad, the distal node being 

 approximately midway the base of the lower finger. The latter 

 is a broad, short triangle, with seven or eight teeth along the 

 cutting edge and a stronger, longer, curved apical tooth. The 

 hinged finger is longer, slenderer, curved, swung obliquely. The 

 inequality between the right and left chelae characteristic of 

 Calappa exists in this species, as shown in plate 73. 



The ambulatory legs are slender, decreasing in size from the 

 first to fourth pairs. 



References : Cancer philargitts, Linne, C. von, Syst. Nat. 1767, 

 Ed. XII, p. 1042. 



Calappa philargius, de Haan, Fauna Japonica, 1850, p. 71, pi. 19, 

 fig. 1, pi. E.— Parisi, B., Atti Soc. Ital. Sc. Nat. 1914, t. LIII, 

 p. 284 (with extensive references) . — Ihle, J. E. W., Siboga 

 Expeditie, Decap. Brachyura, III, Oxystomata, Monogr. 

 XXXIX-b-2, 1918, Leiden, p. 183 (with additional refer- 

 ences). 



