PERU 



641 



phoromoea, lAiliea, Banisteria, Tapiria, Vochysia, and other South Amer- 

 ican types, and denotes a mesophytic tropical environment. 



Peru 



From near Tnmhez (locality number 6), on the coast of Peru, I have 

 recently described a small flora of 14 species,^ of which several are oidy 

 tentatively identified because of the fragmentary nature of the material. 

 Seven of these species are common to the Tertiary of Colombia, one is 

 found in the Culebra, Gatun, and Caimito formations of the Canal Zone, 

 one in the Loja basin of Ecuador, one in Chile, and another is close to if 

 not identical with a Chilean form. This flora denotes very different cli- 

 matic conditions from those that prevail at the present time in this semi- 

 desert coastal region. 



The plant localities in Colombia and Ecuador represent continental 

 deposits and lack marine faunas. In the case of Tumbez, however, we 

 are dealing witli lagoonal deposits intercalated in a marine fossiliferous 

 series, so that the evidence of the flora can be checked by a certain amount 

 of faunal evidence. The general section of the Tertiary of the coastal 

 region of Peru is segregated by Grzybowski^ into the following units, to 

 which he assigns the ages as given below : 



Paita stage Pliocene 



Talara stage • Upper Miocene 



Zorritos stage Miocene 



Heath stage Lower Miocene 



Ovibio stage Oligoeene 



The fossil plants come from the Heath stage. The small fauna found 

 in the associated beds of this stage comprise 19 species, representing the 

 genera Area, Turritella, Pyrula, Puncturella, Ostrea, Venus, Cytherea, 

 Cardium, Lutraria, Dosinia, Leda, and Lucina. Venus milnsteri and 

 Lutraria vetula are common to the Favidad beds of Chile, Cytherea plani- 

 vieta occurs in the Bowden marl of Jamaica, and Turritella altilirata in 

 the Gatun formation of the Canal Zone. The genera Lutraria, Ostrea, 

 and Cardium have closely related species in the Navidad beds of Chile, 

 and Dosinia is represented by a closely related species in the Miocene of 

 the Island of Trinidad. The Bowden marl has been shown to be of 

 Burdigalian age by Woodring, while the Gatun formation, according to 

 Douville and Vaughan, represents both Burdigalian and Helvetian. The 



8 E. W. Berry : U. S. National Museum, Proc, vol. 55, 1919, pp. 279-294, pis. 14-17. 

 ^ J. Grzybowski : Die Tertiiirublagerungen des nordlichen Peru und ihre Mollusken- 

 fauna. Nenes .Tahrb. Beil., Bd. 12, 1899, pp. 010-664, pis. 15-20. 



