506 PRO'CEEDm-GS OF THE NATIONAL MUSEUM vol. 91 



pace also begins to slope down toward the orbits; epigastric promi- 

 nences coarsely punctate, not very conspicuous, low swellings. 



Extraorbital sinus very small, at times obsolescent and represented 

 by no more than a definite, usually abrupt, often nearly right-angled 

 offset between the outer end of the orbital margin and the inner slope 

 or margin of the anterolateral spine; an orbital spine, or rather 

 spinule, generally present, usually much reduced in size. 



Anterolateral spines relatively small, moderately slender, reaching 

 at least to middle of cornea and often beyond. Anterolateral angle 

 of first hepatic lobe fairly well marked, little produced, subacute ap- 

 pearing, though scabrous, and tipped with a corneous scale or two 

 of about the size of, or very slightly larger than, the scattering of 

 similar scales on the lateral margin of this lobe; second and third 

 lobes set off from the preceding and each other by a short, though 

 plainly marked and nearly closed, notch or incision. 



Larger hand relatively of good size, moderately thick and swollen, 

 finely scabrous, though appearing smooth and evenly rounded. Mov- 

 able finger with a small but evident, anteriorly spined lobe on outer 

 margin near base; outer margin of palmar crest more or less sub- 

 parallel to upper margin of palm proper, cut into three or four 

 scabrous-margined shallow serrations; with rare exceptions the an- 

 terior end of upper margin of palmar crest ends abruptly a little 

 distance behind dorsal anterior margin of palm posterior to the base 

 of the movable finger, so that a more or less sharply right angled 

 notch is formed between anterior end of palmar crest and anterior 

 dorsal margin of palm (a somewhat similar, though less noticeably 

 and less well developed notch occurs in the subspecies of A. laevis 

 described below, in A. neuquensis, perhaps also in A. affmis, in 

 A. riolimayana^ and to some degree in A. dbtao though in most if 

 not all other species of Aegla any comparable notch is scarcely to be 

 distinguished from the toothing or serration of the palmar crest 

 itself) . The palmar crest of A. laevis is fairly thin, and slightly exca- 

 vate or troughed adjacent to the margin of the palm proper. 



Ridge of carpus of cheliped above spined, inner margin more or less 

 obsolescently nodulated (on the carpus of the minor cheliped of one 

 male the anterior "nodulations" have taken on a distinctly tubercular 

 form; ordinarily the nodulations on this ridge are low and little 

 scabrous) ; anterior internal lobe or angle of carpus obtusely tri- 

 angular, apically carrying two or three stout, pointed, conical, corne- 

 ous scales ; spines of inner margin stout, conical, and acutely corneous 

 tipped. Upper longitudinal margin of merus furnished with series 

 of apically scabrous, raised tuberculiform elevations, of which the 

 anteriormost is the largest; middorsal point of anterior margin of 

 merus without rode or swelling and otherwise unarmed or unorna- 



