THE SUB-TROPICAL ZONE. 141 



and that part of Mexico belonging to this zone, only a few 

 of the broader features can be given. The evergreen cha- 

 racter between 30 and 36 of latitude is chiefly produced 

 by the Laurels and splendid Magnolia-trees, by Ilex vomi- 

 toria, Pines, etc. ; the green leaves of the Oak too are seen 

 interspersed; Kalmias, the American Olive, etc., are like- 

 wise amongst the list of evergreen trees and shrubs with 

 "large, shining, deep green leaves, which have sometimes 

 astonishingly large and fragrant flowers," and are a distin- 

 guishing mark of this part of North America, The North 

 American portion of this zone differs in many respects from 

 the Old World countries contained in it. For instance, 

 there are vast forests of Cypress on the lower part of the 

 Mississippi and in Mexico, the trees of which are covered 

 with a tropical parasite, called Tillandsia mneoides, a well- 

 grown plant with perfect leaves and handsome red flowers, 

 which, contrasted with the splendid background formed by 

 the dark Cypresses, must be not only a peculiar but a most 

 beautiful sight. Dicotyledonous trees are less frequent in 

 these regions, and the little Pan-palms, called C/iamcerops 

 Palmetto, begin to " appear in greater or smaller numbers, 

 often in extensive social masses, where a marshy soil favours 

 their propagation," and excite a desire in our minds to see 



