530 BULLETIN 129_, UNITED STATES NATIONAL MUSEUM 



Measurements.— Female (3270), length of carapace 32.4, width 

 of same 39.2, length of right arm 18.4, length of propodus of right 

 cheliped 31.3 mm. 



Range. — Manzanillo, Mexico, to Panama. 



Material examined. — Panama; Capt. John M. Dow, collector; 1 

 female (3270). 



TUTANKHAMEN, new genus 



Type.—Mesorhoea cristatipes A. Milne Edwards. 



Diagnosis. — Having the dorsal aspect of Parthenope, but resembling 

 Mesorhoea in its deep afferent channels. The channels, however, 

 differ markedly from those of Mesorhoea in being shorter and deeper, 

 bordered above by a laminar expansion of the hepatic and anterior 

 branchial margins, below by a parallel lamina having an emargina- 

 tion near the beginning of the branchial regions; the canals terminate 

 in a cul-de-sac behind the orbit and open on the epistome by a fissure 

 between the external angle of the thin lamina which forms the anterior 

 edge of the buccal cavity and a sort of promonotory formed by the 

 infero-internal angle of the orbit. Epistome spacious and very 

 concave, separated by a thin ridge and a considerable interval from 

 the antennules. 



Merus of maxilliped without the antero-internal angle produced 

 forward in a point, as in Mesorhoea, or emarginated for the insertion 

 of the palpus as in Parthenope. 



This genus, typified by the so-called Mesorhoea cristatipes, has no 

 obvious resemblance to the true Mesorhoeas, which are Solenolambrus- 

 like in dorsal view and were placed in that genus by A. Milne Edwards. 

 The new genus is created at the suggestion of Prof. Bouvier, from 

 whose detailed description of the ventral surface the above diagnosis 

 is abstracted. 



TUTANKHAMEN CRISTATIPES (A. Milne Edwards) 



Plate 277, figs. 3-5 



Mesorhoea cristatipes A. Milne Edwards, Crust. Reg. Mex., 18S0, p. 352, 

 pi. 31A, figs. 6-6c (type-locality, St. Vincent, 124 fathoms; type in Paris 

 Mus.); Bull. Mus. Comp. Zool., vol. 8, 1880, p. 5. — A. Milne Edwards 

 and Bouvier, Mem. Mus. Comp. Zool., vol. 47, 1923, p. 359, pi. 10, fig. 3. 



Lamhrus cristatipes Rathbun, Bull. Lab. Nat. Hist. State Univ. Iowa, vol. 

 4, 1898, p. 261. 



Diagnosis. — Carapace sub triangular. Rostrum large, deeply tri- 

 lobed. Lateral teeth small. Legs unarmed. 



Description. — Carapace smooth, outline almost triangular; gastric 

 and cardiac regions very high forming a median elevation; three 

 tubercles, one posterior and median, the others anterior and lateral, 

 ornament the gastric region; two obtuse, median elevations on cardiac 



