.278 BULLETIN 152, UNITED STATES NATIONAL MUSEUM 

 GAUDICHAUDIA, new genus 



Type. — Xantho gaudichaudii Milne Edwards. 



Diagnosis. — Near Xantho. Front one-fifth of carapace-width; 

 margin thick, appearing double-edged, bilobed, lower or true edge 

 quadrilobulate. Orbits subcircular, edge subentire, three sutures 

 faintly indicated. Basal article of antenna broad, touching front; 

 first movable article broad, situated in the orbital hiatus. Epistome 

 slightly produced at middle. Antero-extemal margin of merus of 

 outer maxilliped nearly transverse; antero-internal margin not deeply 

 notched, but sinuous or somewhat trilobed. Legs broad, thick, and 

 rough. Otherwise as in Xantho. 



Contains onlj'^ one species. 



GAUDICHAUDIA GAUDICHAUDII (Milne Edwards), new combination 



Plates 126 and 127 



Xantho gaudichaudii Milne Edwards, Hist. Nat. Crust., vol. 1, 1834, p. 396 

 (type-locality, Chile; type in Paris Mus.). — Milne Edwards and Lucas, 

 d'Orbigny's Voy. Amer. Mer., vol. 6, pt. 1, 1844, p. 15; vol. 9, atlas, 1847, 

 pi. 5, fig. 4.— Rathbun, Proc. U. S. Nat. Mus., vol. 38, 1910, p. 540, pi. 39, 

 fig. 1 (after Milne Edwards and Lucas) . 



Xantho bifrons Ortmann, Zool. Jahrb., vol. 7, 1893, p. 450, pi. 17, fig. 7 (type- 

 locality, Ancon 5' Gulf; type in Strassburg Mus.). 



Xantho gaudichaudi Ortmann, Zool. Jahrb., vol. 10, 1897, p. 296. — Lenz, Zool. 

 Jahrb., Suppl. 5, vol. 2, 1902, p. 760. — Porter, Revista Chilena Hist. Nat., 

 vol. 9, 1905, p. 32, text-fig. 1. 



Diagnosis. — Margin of carapace thick. Edge of front ^vith four 

 small lobules. Margin of orbit subentire. Four antero-lateral lobes, 

 the first one almost obsolete. Upper margin of merus of ambidatory 

 legs spinulous. 



Description. — Surface punctate and under the lens finely and 

 closely granulate. Areolation fairly well marked; a deep longitu- 

 dinal groove runs back from the fronto-orbital notch. Antero-lateral 

 margin very thick, without tooth at orbit; first lobe low, obscure; 

 next three lobes slightly prominent or dentiform with very blunt tips. 

 Sinuses of front U-shaped, the lateral ones broadly so; both edges of 

 front coarsely granulate. Inner supra-orbital tooth well marked and 

 well separated from the front. 



Chelipeds unequal in both sexes, heavy; upper margin of merus 

 denticulate, a shallow subdistal sinus ; carpus with a short blunt inner 

 tooth and a more obscure one below; manus widening distally; the 

 black of the fingers covers all but the tips and the extreme proximal 

 end of the dactylus, and extends from the immovable finger back a 

 little on the palm. Ambulatory legs rough and hairy; merus spinu- 

 lous on upper margin; carpus and propodus more or less sharply 



" Ecufidor. 



