of the Mountains of Sta. Marta. 165 



sea (Caracas, Sta. Marta) attained nearly their present eleva- 

 tion above the sea-level at their first upheaval, and were only 

 a little further uplifted at the close of the Cretaceous* and 

 Tertiary epochs, while the present Cordillera, extending south- 

 wards, remained still covered by the sea, and only attained its 

 present form and elevation in this direction by means of the 

 eruption of the trachytic masses and lavas, which occurred 

 most powerfully in the south (Ecuador) and diminished 

 gradually northwards (Geologie, p. 51). 



The existing Sierra Nevada de Sta. Marta, like the moun- 

 tains of Caracas, was already almost completely upheaved 

 above the Cretaceous sea and still more completely above the 

 sea of the succeeding Tertiary formation, as may be recog- 

 nized from the conditions of stratification of the Neptunian 

 deposits. 



Whilst the Cordillera of New Granada and Ecuador, espe- 

 cially in its trachytic portions, is generally overlain nearly to 

 the highest summits by strata of the Tertiary epoch, the two 

 Plutonic mountain-masses of the north coast bear Tertiary 

 deposits only up to small elevations (Geologie, pp. 12, 23, 52). 



The two geographers, Simons and Siveis, the latest writers 

 upon the Sierra Nevada, do not enlarge our knowledge of this 

 geological question. 



Simons (Proc. Roy. Geogr. Soc. 1879, 1881, and 1885), as 

 the fruit of his investigations of the Sierra Nevada extending 

 over several years, gives us an excellent geographical Map, 

 the first and best of the original maps of this region founded 

 upon personal surveys (Proc. li. G. S. 1881), as a com- 

 pletion of the admirable work of Codazzi, who, as is well 

 known, perished under the deadly climate of the plains at the 

 commencement of the survey of this province. 



Upon the geological characters of the Sierra Nevada Simons 

 says nothing. The traveller Sivers, who followed him (Zeitschr. 

 cler Gesellsch. fur Erdk., Berlin, 1888), adheres, as regards 

 geology, to the results obtained by me (p. 57), saying upon 

 the age of this mountain-massif, " It appears, therefore, that 

 the Sierra Nevada de Sta. Marta is a very old piece of the 

 earth's crust which had enjoyed a long continental period 

 when the flooding of its margins by the Cretaceous sea com- 

 menced. After these deposits had lasted throughout the 



* Steinmann's statement that the Jurassic formation also occurs iu 

 New Granada {Neues Jahrb. der Min. Sec, 1882) has proved to be erro- 

 neous. The Jurassic formation indicated by me, in consequence of Stein- 

 mann's publication, in my Map in the " Geoloyie, &c."' is consequently to 

 be altered to Cretaceous. 



