OP ARTS AND SCIENCES. 133 



Walter Faxon, and Cat. No. 3575 (male, form II.), from Bradford, 

 Ind., A. S. Packard, Jr., probably belong to this species, but the speci- 

 mens are too young to determine with confidence. 



This species resembles G. spinosus, from which it is easily distin- 

 guished by tlie length of the posterior section of the carapace, and by 

 the length of the male appendages. From C. affinis it may be sepa- 

 rated by the different form of the male appendages and female annu- 

 lus ventralis, and by the single lateral |pine of tlie carapace. I have 

 seen males of the first form only 34 mm. in length. 



20. C. FORCEPS, sp. nov. 



Male, form I. Rostrum narrow, excavated, faintly carinated in the 

 middle ; margins divergent at the base, thickened, dotted-lined ; acumen 

 long and narrow, horny tii^ped ; lateral spines small. Post-orbital 

 ridges not very prominent except anteriorly, where they terminate in 

 a spine with a corneous tip. Carapace cylindroidal, punctate above, 

 granulated on the sides, antero-lateral margins bluntly angulated; 

 cervical groove sinuate ; small and acute lateral spine : no branchios- 

 tegian spine ; areola of moderate width, punctate. Abdomen as long 

 as the cephalo-thorax : telson rounded behind, bispinose on each side. 

 Epistoma smooth, anterior process triangular, in some specimens trun- 

 cate. Thoracic sterna with silky setae at bases of the legs. Antennae 

 slender, as long as the body ; scale a little longer than the rostrum, of 

 moderate width, sub-truncate at distal end, outer margin ending in a 

 long, sharp, somewhat outwardly directed spine. Third pair of maxil- 

 lipeds hairy within. Chelipeds short, stout; chelag large, wide, with 

 slender cylindrical, widely-gaping fingers, which are curved outward 

 at the base and opposable only at their tips ; hand thickly punctated 

 above and below, inner margin obscurely serrate ; fingers naked at 

 base, with parallel rows of ciliated dots ; a dark band around both the 

 inner and outer fingers a little distance from the tip. Carpus punctate 

 above, a strong, sharp internal median spine ; below there is no ante- 

 rior median spine, and only a very minute external one. Meros short ; 

 of the biscrial inferior spines only the distal one in each row is usually 

 developed to any extent; above there are commonly two obliquely 

 placed ante-apical spines, in some specimens only one. Distal portion 

 of the following pairs of legs furnished with long setae, especially long 

 on the second pair of legs. Third segment of third pair of legs hooked. 

 First pair of abdominal appendages long, deeply bifid, rami slender, 

 straight, parallel, the outer a little longer than the inner, and a little 

 recurved at the tip. In some specimens the anterior border at the 



