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row and ending anteriorly into a rather long, triangular, depressed spine, with the 

 tip acuminate. The chela is as long as the anterior margin of the front; the palm is smooth, 

 but covered with very minute granules when examined under some magnification, shorter than 

 the fingers; the granules are arranged in some oblique rows near the carpal joint, and the 

 upper margin is elevated into a depressed lobe, which occupies, as Miss Rathbun 

 remarks, the proximal two-thirds of the margin; the outer surface of the palm is somewhat 

 prominent near the carpal joint: a very indistinct horizontal line runs from the carpal joint to 

 the tip of the fixed finger, and a trace of a second (oblique) line is visible above it on the 

 palm; the fingers are very high at the base, largely compressed, very slightly spooned at the 

 lip; the back of the mobile finger is covered with minute granules, and the cutting margin is 

 provided with about 13 obtuse teeth, that are largest in the middle; that of the fixed finger 

 has proximally 6 teeth, increasing gradually in size, so that the two terminal ones are very 

 large, then follow two small teeth and at last a much larger tooth at the beginning of the 

 horny extremity of the finger. 



Walking legs long and .slender, the penultimate pair being 1Y3 times the maximum 

 breadth of the carapace. Meropodites about 37. times as long as broad, with a sharp subdistal 

 tooth at the anterior margin, except in the case of the terminal pair of legs ; both anterior 

 and posterior margins with short hairs, intermingled with longer hairs; above the bases 

 of the legs clusters of club-shaped hairs are observed. Carpo- and propodite together are as 

 long as the meropodite; both margins are fringed with hairs, especially at the hind margin 

 of the much flattened propodite, that is paddle-shaped, and longitudinally-oval in the posterior 

 legs. Dactyli falciform, depressed, as long as the hind margin of the preceding joints, and 

 likewise fringed. 



Certainly this species is nearest to Pt. spinicarpus Ortmann, with which also Miss 

 Rathbun compares it; the carapaces of both species seem to resemble each other very much, 

 but the exognath of Ortmann's species is twice as broad as the ischium of 

 the external maxillipeds, whereas it is only \^\„ times of the width of the latter in the 

 present species. In other respects there is a very great resemblance, for the spine at the wrist 

 of the cheliped is exactly alike, and even the small tubercle at the base of this spine and at 

 the anterior margin of the wrist occurs in both species; again, the fingers of the chelae are 

 likewise much depressed and the teeth at the cutting margin of the fixed finger show much 

 the same disposition; the upper border of the palm is in Pt. spinicarptis likewise transformed 

 into a compressed, rather sharp lobe '). There seems to be some difference in the abdomen of 

 the cT, which is generally of a more narrow shape in Pt. altimanus; that of Pt. spinicarpus 

 as depicted by Ortmann '-) is probably inexact, as the terminal segment presents an unnaturally 

 elongated and asymmetrical shape, but de Man states, that 'it resembles that of Pt. dentatus 

 and the abdomen of the latter^) is decidedly much broader, with the lateral margins more 



1) Miss Katiibu.n quotes the absence of this lobe in Ortmann's species as a ditTcience between the two species, but bolli 

 Ortmann and afterwards de Man slate, that the palm is compressed above. 



2) Zool. Jahrb., Syst., Bd 7, 1894, pi. 23, f. 13:. 



3) Weber's zool. Erg. Keise niederl. Ost-Indien, Bd 2, 1892, pi. 18, f. <)b. 



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