ORTMANN I TERTIARY INVERTEBRATES. 255 



Distribittion : Living from Tierra del Fuego along the western coast of 

 America to California, and along the eastern coast to Brazil (Darw., 

 Weltn.). Fossil in the Pliocene Coquimbo beds of Chili (Sow., Darw., 

 Phil.), and subrecent in Peru (Darw.). 



DECAPODA. 

 Fam. CARCINOPLACID^E Ortm. 



Gen. GERYON Kroy. 

 1 80. GERYON (?) PERUVIANUS (d'Orbigny). 



PI. XXXVIII, Fig. 6"'". 



1842 Portunus peruvianus d'Orbigny, in : Voy. Amer. merid., v. 3, p. 107, 



pi. 6, f. 17. 

 1860 Carcinus p. A. Milne-Edwards, in: Annal. Sci. natur., ser. 4, v. 14, p. 



69, pi. 8. ' 

 1887 Cancer patagonicus Philippi, Tert. & Quart. Verst. Chiles, p. 220, pi. 



50, f. i. 



1900 Geryon (f] peruvianus Ortmann, in : Amer. Journ. Sci., v. 10, p. 381. 

 Carapace with the regions hardly distinguishable, subpentagonal, sur- 

 face fin-ely granulated. Front with four tooth-like lobes. Orbits trans- 

 verse, each a little broader than the front, with a closed fissure in the 

 upper margin. Antero-lateral margin curved, a little shorter than the 

 straight postero-lateral margin, with 5 teeth, the first of which is the extra- 

 orbital tooth ; teeth conical, pointed, separated by broad, concave inter- 

 vals. Sternum broadly oval. Abdomen of the male triangular, that of 

 the female ovate. Third maxilliped of the usual Brachyuran type, with an 

 almost quadrate meropodite, at the anterior inner angle of which the car- 

 popodite is inserted, and with a well-developed exopodite. First pair of 

 pereiopods strong, a little unequal ; meropodite triangular, stout ; carpo- 

 podite short and stout, with a tooth on the inner side; hand elongate- 

 oval, fingers strong, a little shorter than the palm, with inner edges 

 strongly dentate. Meropodite of the 4 posterior pairs of pereiopods 

 strong and rather elongate, compressed, with a blunt edge on the upper 

 margin. 



