A New Ammonite Fauna of the Lower Turanian of Mexico 183 



40. Yabe, Strat, u. Pal. Hokkaido. H. Yabe, Zur Stratigraphie und Palaontologie 



der oberen Kreide von Hokkaido und Sachalin. Zeitschr. d. Deutsch. geol. 

 Ges. Bd. 61, 1909. 



41. Zittel, Lib. Wiiste. K. A. Zittcl, Beitrage zur Geologie und Palaeontologie der 



Libyschen Wiiste und der angrenzenden Gebiete von Aegypten. I. Geolo- 

 gischer Theil. Palaeontographica Bd. 30, I. 1883. 



STRATIGRAPHY 



The Cerro del Macho is a small hill in the eastern part of the Hacienda 

 del Mohovano belonging to Mr. Frederick Ritter. The hacienda lies to the 

 southeast of the station Carillo of the railway which connects Sierra Mo- 

 jada, Coahuila with Escalon, Chihuahua (Mexican Central Railway) and 

 part of its land belongs to the State of Chihuahua while the rest lies in the 

 State of Coahuila. The Cerro del Macho belongs to this last region and 

 lies near the boundary line of both states. 



Dr. E. Haarmann gave me the following geological cross-section of the 

 fossiliferous locality, to which I add the stratigraphical explanation ob- 

 tained as the result of the study of the fauna. 



-JT 



Fig. 1 



Fossil bearing beds on the Cerro del Macho, Hacienda del Moh6vano, 

 Coahuila. 



III. Gray hard limestones "1 



II. Gray-bluish marls J 



I. Yellow and red marls and argillaceous limestones Upper Cenoman- 



Lower Turonian. 



Three different petrographical horizons can be distinguished : the low 

 est beds consist of yellow and red marls with argillaceous limestones con- 

 taining numerous fossils, especially bivalves; this horizon which for the 

 present we shall designate with the number I has a thickness of only two 



