| OCR Text |
Show 1 9 0 5 .] FROM CHRISTMAS ISLAND. 5 4 5 different localities of the Indian Archipelago, described, in 1892, in my paper on the Decapod Crustacea collected by Prof. Max Weber, are lying before me, as also are specimens from my own collection. When the young male from the River Palopo on the island of Celebes (de Man, in Max Weber, Zool. Ergebnisse, ii. 1892, p. 447) is compared with the male from Christmas Island, a doubt occurs to me whether we are right in considering these two Prawns as belonging to one and the same species. The male from the River Palopo (PI. XVIII. figs. 16-19) is certainly a typical example of Pal. lar Fabr., but in the male from Christmas Island, the size of which is even a little smaller, all the legs have a much stouter shape, and there are no doubt still other differences. Specimens of Eupalcemon, presenting the same characters as this male from Christmas Island, have formerly been referred by me, and no doubt also by other authors (because this form is probably also widely distributed thr oughout the Indian Archipelago), to the " well-known " Pal. lar Fabr.; but it appears to be a question tohether this form may still be regarded as a variety or not. I do not venture to decide this question at present, because the specimens are apparently young, but I wish to draw the attention of carcinologists to it, confining myself at present to describing the specimens from Christmas Island accurately. These Prawns are, no doubt, young; the male is 62 mm. long from the tip of the rostrum to the end of the telson, the female 43 mm. The carapace of both is smooth. The lanceolate rostrum (PI. XVIII. fig. 7) of the male is rather short, shorter than the peduncles of the internal antennae, reaching but a little beyond the 'penultimate joint of these peduncles. The upper border, slightly arcuate above the eyes, is somewhat directed downward, though the acute tip extends horizontally forward; it carries eight equidistant teeth, that reach to the tip. The first two teeth stand on the carapace, the third just before the frontal margin, above the insertion of the eye-peduncles, and these teeth diminish a little in length from the second, that is the longest, to the last one. The distal half of the lower border carries three equidistant teeth that are smaller than those of the upper border, and the first of which is situated just below the antepenultimate tooth of the upper border; the acute tip of the 3rd is a little farther from the extremity of the rostrum than from the tip of the 2nd tooth. At the level of the 1 st tooth of the lower margin the rostrum is just as broad above as below the lateral carina, and the height of the rostrum at its base is a little larger than its breadth below that carina. Hepatic and antennal spines as in typical specimens of Pal. lar. Of the two pairs of spinules on the upper surface of the telson, the anterior is inserted on the middle, the posterior midway between the anterior pair and the tip of the telson. The telson ends posteriorly in a sharp tooth ; the inner of the two spines on either side projects half its length beyond the median tooth, whereas the outer spinule, barely half as long as the inner, reaches not so far backwaid as the median |
