[03] DECAPODA FROM ALBATROSS DREDGINGS. 407 



successively from the tbiixl, which scarcely reach the tips of the second 

 guathopods to the first, which only reach the bases of the chela? of the 

 third. The first pair are a little stouter than the others and sparsely 

 setigerous, while the second and third are nearly naked. The meri all 

 reach to about the same point; the carpi increase successively in length 

 from the first, which is about two-thirds as long as the merus, to the 

 third, which is about twice as long as the first; the chela? increase very 

 slightly in length, but not at all in thickness, from the first to the third, 

 and all are slender, subcylindrical, Avith slender and nearly straight 

 digits, considerably longer than the body of the chela. The fourth and 

 fifth pairs of peneopods are alike, considerably longer than the third 

 pair, reaching to about the tips of the antenna! scales, very slender, and 

 nearly naked, and in each the merus is about as long as the carpus and 

 propodus combined, the carpus about as long as the propodus and dac 

 tylus combined, and the dactylus about half as long as the propodus, 

 slender and very slightly curved. 



The pleou is about twice as long as the carapax excluding the ros- 

 trum, broad anteriorly, not compressed laterally, the first, second, and 

 third somites broadly rounded above, and the first and second unarmed, 

 but the third and the fourth each armed with a stout laterally compressed 

 spiniform tooth directed back over the succeeding somite. The fifth 

 somite has a conspicuous dorsal carina terminating in a sharp tooth like 

 that on the fourth, but much smaller. The sixth somite is about as long 

 as the fourth and fifth combined, about three-fifths as high as long, 

 compressed and conspicuously carinated above, the carina terminating 

 in a small tooth over the base of the telson. The pleura are all trun- 

 cated below, the first and second rounded in outline behind, the third 

 with an obtusely rounded angle, and the fourth and fifth with a minute 

 mucronation at the otherwise obtusely rounded angle. 



The telson is about once and a third as long as the sixth somite, narrow, 

 regularly and acutely triangular, rounder above, and armed with a very 

 few inconspicuous dorso-marginal aculei below the middle. The inner 

 lamella of the uroi)od is shorter than the telson, but reaches by its tip, is 

 ovate-lanceolate in outline and about three and a half times as long as 

 broad. The outer lamella is rather longer than the telson, proportionally 

 about as broad as the inner, with the outer edge rod-like and terminating 

 in an acute tooth some distance from the ovate tip of the lamella. 



The pleopods are all highly developed and the basal portions very 

 large, stout, and nearly alike. The outer rami, in both sexes, are very 

 long, slender, and subcylindrical, those of the anterior pair nearly or 

 quite as long as the five anterior somites taken together, and the posterior 

 about half as long as the anterior. The peculiar appendage of the first 

 pair of pleopods in the male is a squarish plate attached by one corner 

 near the middle of the protopod, the dorsal edge thickened and distally 

 separated from the plate as a slender stylet not projecting beyond the 

 plate itself, and with a notch in the outer edge, from which a fold extends 



