FROM THE INDO-PACIFIC AND WEST AFRICA. 295 



The carpus bears on its outer side a longitudinal ridge along its whole length, and this 

 ridge is continued for a short distance, about 1*5 mm., along the outer margin of the 

 palm. Both merus and carpus bear, moreover, on their upper surface an impressed 

 longitudinal line, which runs in the same direction from the distal end of the ischium to 

 that of the carpus (fig. 6). The hand is 13 mm. long, the palm measures 7"5 mm., the 

 fingers 5'5 mm. ; the palm is thus somewhat longer than the carpus and the fingers, and 

 the proportion between palm and fingers also conforms to the original description, 

 according to which their proportion should be as 3 : 2. The lateral margins of the palm, 

 which is 2 mm. broad in the middle, are parallel with each other, so that its upper surface 

 presents the same breadth almost 'along its whole length ; the palm is 1'5 mm. thick in 

 the middle, so that it appears a little compressed in the proportion q/" 4 : 3. The fingers 

 shut close together and are somewhat curved inward, so that the inner margin of the 

 hand runs very sliglitly concave ; the fingers are also a little broader than thick 

 and they have the same breadth to near their acute tips. Each finger bears a sharp 

 cutting-edge, at the proximal end of which is seen a small conical tooth ; the dactylus 

 bears, moreover, a second tooth between it and the articulation, so that the tooth of the 

 immobile finger is situated just between the two of the dactylus. One observ(!S on each 

 side of the cutting-edge the usual short hairs as in other species, and on the vipper and 

 lower surface of the fingers small tufts of short hairs, which are somewhat longer near 

 the tips, but otherwise the fingers are quite smooth. The straight inner border of the 

 palm is beset with very small spinules, 012 mm. long, visible only Ijy means of a 

 magnifying-glass ; still smaller ones are seen on the outer margin ; the lower surface of 

 the palm bears also a few microscopical spinules, but the upper is nearly smooth. The 

 palm is also a little hairy ; the hairs are short, fine, and widely separate. The other 

 joints of these legs are everywhere covered with similar small spinules and similar short 

 fine hairs. The second legs are 32 mm. long, measuring just two-thirds the length of 

 the animal ; they have a pale flesh-colour. 



The three posterior pairs of legs are short and stout. Those of the third pair reach 

 nearly to the end of the antennal scales, the tw o others are but little shorter. The 

 meropodites of the third pair (fig. 8) are 5 33 mm. long, measured along their upper 

 margin, and 1 mm. thick on their outer side; the propodites are 5 mm. long and 0*72 mm. 

 broad in the middle, the terminal joints finally are 19 mm. long. The meropodites of 

 these legs are ihxx&five, the strongly compressed propodites seven times as long as broad 

 on their outer side, and the terminal joints are little longer than a third of the propodites. 

 The propodites are armed witli nine mobile spines along the posterior margin of their 

 upper and lower surfaces ; these spines measure 0-32-0-38 mm., and are about half as 

 long as these joints arc broad. The propodites arc a little hairy on their upper and on 

 their lower surface, as also along their anterior margin, but are otherwise smooth; the 

 other joints are also a little hairy and almost smooth, though a few microscopical spinules 

 may be distinguished under the microscope. 



Palccmon asperulus should very likely be referred to the subgenus Parapalcemon. 



Those species with which P. asperulus is most closely allied are P. [Parapalcemon) 



