LATEE TERTIAEY (MIOCENE AND PLIOCENE). 797 



E 14^15, F 14 AND 16, G 13 AND 14, AND H-I 11. MEXICO. 



Several localities at which the Miocene or Pliocene have been identified in 

 Mexico are mentioned by Aguilera/® and are here referred to under the index 

 headings enumerated above. A general account of the Tertiary of Mexico is given 

 by Felix and Lenk.^^ The local occurrences are the same as those given by AguUera, 

 but it is profitable to refer to their lucid and connected description. 



E 14. OAXACA. 



The Pliocene of Paso Real, at Tuxtepec, in Oaxaca/' includes conglomerates of 

 old crystalline rocks which overhe sands and white sandstones and contain Pecten 

 (Euvola) bowdmensis Dall, Lcevicardium sublineatum Conrad, Calliostoma cf . linuum 

 Dall, Anguinella virginica Conrad, Xenophora cf . conchyliophora Born, Natica can- 

 rena L., Natica (Polynices) perspectiva Rogers, Strombus pugilis L., Sconsia sub- 

 Imvigata Guppy, Pyrula papyratia Say, Melongena (Solenistra) mengeana Dall, 

 Marginella wilcoxiana Dall, Marginella cinerarea Dall, OUva cf . litterata Lamarck, 

 Pleuritoma (Drillia) alesidota Dall, Conus cf . verrucosus Brugui^re. 



E 15. CHIAPAS. 



In Chiapas,®* in the vicinity of Simojovel, the Miocene is composed of dark 

 argillaceous shales, blue clays, brown sandstones, and interbedded limestone of a 

 white color, which assumes a reddish tint and which extends to the north in the 

 plateau of central Chiapas. The following fossils have been found : Pecten, Ostrea, 

 Turritella, Conus planiceps Heilprin, Clypeaster cf. meridamensis Michelin, etc. 



In the vicinity of Coatzacoalcos, upon the river of the same name, there are 

 white and brown sandstones which contain Amusium papyraceum Gabb, Anomia 

 simplex D'Orbigny, and Lcevicardium sublineatum Conrad, of the Pliocene. 



In the vicinity of Tenejapa, Chiapas, occur marine Phocene rocks consisting of 

 micaceous sandstones and argillaceous shales, together with andesitic tuffs, con- 

 glomerates, and marls which contain Ostrea. This terrane occurs also in the valley 

 of the Rio Chiapas beyond the boundaries of the State of Chiapas. It is found in the 

 hills of .Tabasco, near Macuspana, with Natica canrena; on the frontier between 

 Tabasco and Vera Cruz, near Tenosique; and in the peninsula of Yucatan with 

 Ostrea virginica, Pecten gibbus, Pyrula papyracea, etc. 



F 14. VERA CRTJZ AND HIDALGO. 



In the States of Vera Cruz and Hidalgo ®^ lacustrine deposits of Miocene age 

 occur in the vicinity of Zacualtipan and at Tehuichila. They consist of argillaceous 

 shales with beds of lignite and contain Hippotherium (Hipparion peninsutatum 

 Cope), H. rectidens Cope, and Protohippus castilloi Cope. 



The marine Pliocene is recognized by its fossils at Santa Maria Tatetla, at 

 Papantla, and at Tuxpan, in Vera Cruz. 



r 16. PENINSULA OF YUCATAN. 



The northern portion of Yucatan is occupied by Pliocene and possibly in places 

 by post-Pliocene limestone, which forms a broad plain that rises gradually south- 



