1897-98]. LATE FORMATIONS AND GREAT CHANGES OF LEVEL IN JAMAICA. 349 



Some marls and coast limestones noticed farther west may be the 

 local equivalents of the Liguanea loams and gravels. In the embay- 

 ments of low plains entering the southwestern highlands, this formation 

 seems to be quite extensively represented in the alluviums described by 

 Mr. Brown. On the northern side of the island, the development of 

 the coastal plains is so slight that only fragments of the formation are 

 there preserved. When seen by the writer, no fossils were found in the 

 loams, although a few are reported in some " alluviums." 



Comparison of Liguanea Series with the Zapata of Cuba, and the 

 Lafayette of North America. — In Cuba, the Zapata red loams and 

 gravels* of the same general character and development as the Ligu- 

 anea, and occupying the same general position on the eroded surfaces 

 of the Matanzas, equivalent to the Layton (or late Pliocene?) formation, 

 appear to be the representatives of the Jamaican deposits. 



So also the Columbia loams and gravels, covering 150,000 square 

 miles of the Atlantic and Gulf states, as described by Prof. W. J. Mc- 

 Gee,-|- appear to be the correlative of both the Liguanea and Zapata 

 formations of Jamaica and Cuba. The same formation extends along 

 the eastern side of Mexico to at least as far as the Tehuantepec 

 Isthmus ; and Gabb describes a formation in Santo Domingo that may 

 be included here, and apparently the same formations occur in some 

 of the Windward Islands. The Columbia and Lafayette formations 

 are very widespread, and show some unequal elevations of the land, 

 but no discordance in the succession of physical changes throughout 

 the extent of their development, along the margin of the continent for 

 at least 2,000 or 3,000 miles in length. So also the general uniformity, 

 where known, throughout the encircled Antillean region has a similar 

 character. Although the magnitude of the terrestrial oscillations 

 varied somewhat, and may have commenced and ended earlier in one 

 locality than in another, yet the Liguanea, Zapata and Columbia 

 formations appear to be an expression for the same formation in 

 separated localities. 



That the Liguanea formation is very often seen well stratified at con- 

 siderable elevation near the sea shore, seems sufficient evidence of its 

 origin at sea level, as there could have been no barriers to exclude the 

 oceanic waters, although marine fossil remains in it are not certainl)' 

 established. In this respect, the character is identical with the Colum- 

 bia formation of the continent. It is possible that some of the isolated 



* " Geogr.-iphical Evolution of Cuba," by J. W. Spencer. Bull. Geo!. Soc. Am., vol. vii., pp. 67-94. 

 t Cited before. 



