516 BULLETIN 120_, UNITED STATES NATIONAL MUSEUM 



between branchial and gastric regions. Antero-lateral margin 

 behind cervical sulcus armed with eight triangular, denticulated 

 teeth, the posterior one but little longer than the others which are 

 equal. Front smooth; rostrum of moderate size, sub triangular, 

 deflexed, sides slightly concave, unanned, apex obtuse. Chelipeds 

 long, surface smooth above except of merus which has a median 

 tuberculated ridge; edges of merus, carpus and manus armed with 

 small teeth, which on superior edge of merus are spiniform; outer 

 edge of manus with 16 teeth alternating in size; below, the chelipeds 

 are smooth and glabrous except inner edges which are tuberculated; 

 tubercles small. Sternum with a strongly prominent, almost capitate 

 tubercle on each side at base of chelipeds, which also bear a small 

 tubercle on basal joint; these four tubercles are somewhat flattened 

 at top and bent forward. In the female abdomen the segments are 

 each armed with a transverse ridge, more or less developed; on second 

 and third joints this ridge is strongly toothed and on penult joint it 

 appears in form of a median tubercle. (After Stimpson.) 



Measurements. — Sterile female, holotype, length of carapace 15.2, 

 width of same 17.2, proportion 1: 1.13; length of merus of cheliped 

 15.2 mm. (After Stimpson.) Specimen from Mazatlan, sex not 

 given, length of carapace 29, width of same 32, length of arm 30, of 

 hand 32 mm. (After A. Milne Edwards.) 



Range. — Mazatlan, Mexico (A. Milne Edwards) ; Panama (type- 

 locality) . 



Subgenus Platylambrus Stimpson 



Platylamhrus Stimpson, Bull. Mus. Comp. Zool., vol. 2, 1871, p. 129; type, 

 Lamhrus crenulatus Saussure, 1858 = L. serratus Milne Edwards, 1834. — 

 A. Milne Edwards, Crust. Reg. Mex., 1878, p. 146. 



Enoplolambrus A. Milne Edwards, Crust. R^g. Max., 1878, p. 147; type, 

 L. carenatus Milne Edwards. 



Lamhrus Miers, Challenger Rept., Zool., vol. 17, 1886, p. 92 (part). 



Carapace carinated or tuberculated, broader than long, broadly 

 triangular with rounded sides and a broad but acute and projecting 

 rostrum; no postocular constriction; chelipeds with the meropodite 

 and palm straight, the former joint prismatic, the latter sharply 

 trigonal, the anterior and posterior borders of both joints sharply 

 laciniate or serrate, as is also the outer edge of the carpus. (Alcock.) 



PARTHENOPE (PLATYLAMBRUS) SERRATA (Milne Edwards) 



Plates 180 and 181; plate 275, figs. 7-10 



Lamhrus serratus Milne Edwards, Hist. Nat. Crust., vol. 1, 1834, p. 357, 

 not synonymy (type-locality, I'Ocian indien [by error]; type in Paris 

 Mus.). Not Lamhrus serratus White, List Crust. Brit. Mus., 1847, p. 12. 



Lamhrus lupoides White, List Crust. Brit. Mus., 1847, p. 12, nomen nudum 

 (type-locality, West Indies; type in Brit. Mus.). 



