GEOLOGY AND PALEONTOLOGY OF THE CANAL ZONE. 177 



of chelipeds or legs ; the nodule is very little wider than the carapace. 

 Cat. No. 324228, U.S.N.M. 



Family GECARCINIDAE. 



CARDISOMA GUANHUMI Latreille. 



Plate 64, figs. 2-4. 



Cardisoma guanhumi LATREILLE, Encyc. Meth., Hist. Nat., Insectes, vol. 10, 

 1825, p. 685. 



Locality. Costa Eica : City of Port Limon. Port Limon forma- 

 tion. Pliocene series. Dr. L. A. Wailes, collector. Station 4269. 

 Cat. No. 324263, U.S.N.M. 



Material. Left propodal finger of cheliped, with extremities lack- 

 ing; length 18.5 mm. Pieces of the outer crust remain along the pre- 

 hensile teeth, around the distal end, and on the lower part of the 

 proximal end, where it shows the characteristic scaly granulation of 

 the species. 



Distribution of Recent Material. From Bahamas and Florida 

 Keys to Brazil ; Bermudas. 



Family OCYPODIDAE. 



UCA MACRODACTYLUS (Milne Edwards and Lucas). 



Plate 64, fig. 7. 



Gelasimus macrodactylus MILNE EDWABDS and LUCAS, d'Orbigny's Voy. 

 Amer. Mer., vol. 6, 1843, p. 27 ; vol. 9, atlas, 1847, pi. 11, fig. 3. 



Locality. Panama Canal Zone. From near Mount Hope in ditch 

 through swampy ground. About one-quarter mile from present sea 

 beach, 6 to 8 feet above high tide. Pleistocene series. D. F. Mac- 

 Donald, collector. April, 1911. Station 5850. Cat. No. 324251, 

 U.S.N.M. 



Material. A single dactylus, 6.7 mm. long, of an ambulatory leg 

 corresponds with that of a recent specimen from Costa Eica. The 

 dactylus is rather slender, regularly tapering and strongly curved 

 on its concave as well as on its convex margin, it has 6 longitudinal 

 grooves separated by as many smooth rounded ridges; toward the 

 horny tip these ridges are themselves guttered by a narrow groove. 



Distribution of Recent Material. From Guaymas, Mexico, to Val- 

 paraiso, Chile. 



BRACHYRHYNCHA, family, genus, and species indeterminable. 



Plate 64, fig. 6. 



Locality. Panama Canal Zone. Las Cascadas section, Gaillard 

 Cut. From lowest fossiliferous bed. Third bed below lowest lime- 



