:)70 MEMOIRS OF THE CARNEGIE MUSEUM 



The (iliddmcn, epidoma, anfcniiiild, and (iiitciiiid ai'o also similar to those of ('. 

 [)ropinquut<. 



The fi.rd pcrciopods (Plate XL, Fig. 1) are generally more robust than in ('. pro- 

 'pinquus, particularly in adult males. Hand wider and more distinctly depressed. 

 The fingers more widely gaping in old males, and the S-shaped curve of the movable 

 finger more pronounced ; in old females there is also a slight gap at the base of the 

 fingers. The upper surface of the hand possesses, particularly in large specimens, 

 a small number of scattered low tubercles near the inner margin, and very often 

 (but not always) there is a row of 3-5 tubercles running toward the base of the 

 movable finger, parallel to the inner margin. Tubercles of the outer margin of the 

 dactylopodite more jtrunounced. The sculpture of the hand is rather variable, and 

 must distinctly developed in t)ld males. The shape of the hand is ratlier different 

 in the male and female ; in the female the fingers are shorter, less gaping (or not at 

 all), rendering the outline of the hand more regularly ovate. (See Plate A, Figs. 

 1 and 2.) 



The carpojHjilite differs from that of C. prophiqmis in the development of a 

 strong tubercle on the anterior margin of the lower side. This tubercle very rarely 

 is indistinct (chiefly so in regenerated claws) ; generally it ends in a distinct, stout, 

 conical spine. On the inner margin and on the upper face additional low tubercles 

 are not infre<juently found. 



The meropodite differs from that of ('. projiliKfuus by the constant presence of a 

 series of 4-8 small tubercles, or teeth, behind the distal spine on the imier lower 

 margin. These teeth are never wanting in any of my specimens. The outer lower 

 margin has one or two spines. The latter number is comparatively rare. In re- 

 genei-ated claws very often there is no spine at all on the inner lower margin. 



The other characters of the pereiopods are similar to those of C. pruptitqaus. 



The p'rst pleopnd.^ of male of the first form (Plate XXXIX, Figs, la and Ih) are 

 of the general type of those of T. jirapi ikjuus, but slightly longer, reaching to the 

 anterior margin of the co\o})odites of the third pereiopods. The inner part does 

 not gra<lually taper to the tip, but is of neai'ly uniform thickness, with the tip 

 rounded off and slighth' compressed in tlie antei'o-posterior direction. Sometimes 

 tile tip is even slightly thickened. The anterior margin of this organ, at a point 

 somewhat below the separation of the two parts, has a rather sharp, well marked 

 shoulder, which is absent in none of the specimens at hand (several hundred). 



In the male of the second form (Plate XXXIX, Fig. 7c) this shoulder is missing, 

 and the inner part is blunt, similar in shape to the male of the first form, and not 

 tapering to a point as in the typical ('. pnqjlnqaus. 



