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The first pair of legs exceed the third maxillipeds 

 by two-thirds the length of their fingers and attain the 

 proximal third of the palm of the second legs. In turn, 

 these exceed the tips of the antenna! scales by about 

 three-fifths the length of their hands. The third, fourth 

 and fifth pairs of legs all reach forward about equally 

 far, to about or a little beyond the tip of the antennal 

 scale. Between the bases of the second pair of legs there 

 is a pair of long, slender, anteriorly directed, curved 

 spines; a similar, much smaller pair occurs between the 

 bases of the first pair of legs ; between the third legs is 

 a pair of thickened, blunt, forwardly inclined plates, 

 corresponding in position to the spines between the two 

 preceding pairs of legs. 



The striking abdominal armature of this species is 

 unusual for the genus as known heretofore. Medially 

 on the third somite there is a thickened raised ridge 

 which arises near the anterior margin and running back- 

 ward attains its maximum elevation just behind the 

 anterior third of the somite. Here, in lateral view, it 

 appears to end in a backwardly directed point; viewed 

 dorsally this is seen to be a truncated, tongue-shaped, 

 backward extension of the ridge. The posterior margin 

 of this somite is produced to form a sharp median spine. 

 Similarly placed, but larger, bent, and more laterally 

 compressed spines occur on the fourth and fifth somites. 

 Each of these last-named spines is continuous with a 

 median carina beginning near the anterior third of its 

 respective somite. Anterior to the carina on the fourth 

 somite is a faint impressed line and the carina itself 

 is medially sulcate for slightly less than one-fifth its 

 length. This sulcus begins at about half its OAVH length 

 behind the origin of the carina, and is not connected 

 or continuous with the impressed line preceding it. The 

 carina on the fifth somite is not sulcate, nor is there any 

 impressed line on the somite in advance of it. The sixth 

 somite is dorsally smooth and rounded. Its posterior 

 margin is medially concave and is armed on either side 

 with a spine which projects over the adjacent antero- 

 lateral angle of the telson. Other than the spines just 

 mentioned only the fifth somite is laterally armed. Each 

 of its epimera tapers to an acute spine-like postero- 

 lateral angle, above which there is a second spine situated 

 a little below the articulation of the fifth with the sixth 

 somite. The telson is longer than the sixth somite and 



