hairy toward the extremity. A strong spine on the basal segment of 

 the antenna and a similar spine on each side just behind the orbit. 

 Chelipeds equal, slender, reaching nearly to the distal extremity of 

 the carpus of the first ambulatory legs; ischium with a few small 

 spiues on the inner side ; merus not quite as long as the hand, 

 cylindrical, armed with several spines along the sides, and with three 

 stout ones on the inner side at the articulation of the carpus ; carpus 

 with two or three small spines on the outer side, and two at the 

 distal extremity on the inner side ; basal portion of the hand cylin- 

 drical and smooth, but thickly covered with a minute pubescence; 

 fingers nearly as long as the basal portion of the hand, sparsely hairy, 

 slender, nearly straight horizontally but curved inward laterally at the 

 tips, slightly channelled longitudinally, the prehensile edges approxi- 

 mate, toothed toward the base, and serrate toward the extremity, 

 the serrations of the clactylus fitting accurately those of the propodus. 

 Ambulatory legs slender, cylindrical, and slightly pubescent; meral 

 segments armed with scattered spines, most of which are on the distal 

 two-thirds of the length; carpi with two or three spines about the 

 middle, and four at the distal extremity; propodi armed with small, 

 scattered spines and spinules; dactyli beset with numerous spinules. 

 First segment of the abdomen nearly as long as broad; second 

 broader and very short; third broadest of all the segments, the lateral 

 margins projecting into angles next the second segment and rapidly 

 converging toward the fourth, which narrows very rapidly to the fifth; 

 fifth segment twice as broad as long, the lateral margins at first 

 converging rapidly and then only slightly as they approach the sixth ; 

 terminal article, which is composed of the sixth and seventh segments 

 completely anchylosed, about twice as long as broad, the extremity 

 angular but with the point rounded. Length of carapax, including 

 rostrum, 29.5 mm ; length of rostrum from tip to the posterior side 

 of orbit, 19.0; breadth of carapax, 9.9. Length of cheliped, 34.0; 

 hand, 14.8; dactylus, 7.0. Length of first ambulatory legs, 72.4 — 

 74.2; second, 71.3 — 74.2; third, 58.0; fourth, 50.5. A single speci- 

 men from the Bay of Realejo. 



There are specimens of this species jn the Museum of Yale College, 

 collected at Panama and the Pearl Islands, by Prof. F. H. Bradley, 

 and among these, are females which agree pretty well with the figure 

 of Edwards' and Lucas' L. sagitlaria from Valparaiso, L. debilis, 

 however, differs from the figures of the typical Atlantic sagittaria in 

 the much shorter chelipeds with proportionately much longer fingers, 

 and in the form of the male abdomen, which is very different from 

 the figure of the Atlantic L. sagiUaria given by Edwards in the Eegne 

 animal de Cuvier, and quite like the figure of the yalparaiso species 

 given by Edwards and Lyxas. 



