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NATURALIST'S GUIDE TO THE AMERICAS 



5. JAMAICA 

 BY FORHEST SHREVE 



The island of Jamaica lies between 

 17 and 18 N. latitude and 76 and 78 W. 

 longitude, 90 mi. south of the eastern 

 end of Cuba and almost equidistant 

 from the nearest portions of the main- 

 land of North, Central, and South 

 America. The extreme length of the 

 island is 144 mi., the extreme width 

 49 mi., and the area 4207 sq. mi. The 

 axis of the eastern end of the island is 

 formed by the Blue Mountains, which 

 are the youngest and highest range, 

 attaining 7428 ft. in Blue Mountain 

 Peak. In the center of the island a 

 limestone peak, Mt. Diablo, reaches an 

 elevation of 2300 ft., and just west of 

 it Bull Head is 2885 ft. in elevation. In 

 the southwestern part of the island are 

 the Mocho, Carpenter and Santa Cruz 

 Mountains, all less than 2500 ft. in 

 elevation. Just north of the center of 

 the island is a region nearly 40 mi. 

 long, in which there is an unbroken 

 succession of small limestone hills of 

 nearly uniform height, separated by 

 narrow anastomosing valleys in which 

 lime-sinks are abundant, giving to a 

 portion of the region the name of "Cock- 

 pit Country." The remainder of the 

 island is rolling or hilly, with the ex- 

 ception of the extensive alluvial plains 

 in the south-central portion, the swamps 

 in the south-western corner, and the 

 narrow alluvial plain which follows 

 parts of the coast line. 



With respect to temperature the 

 climate of Jamaica is that typical of its 

 tropical latitude. The rainfall is great- 

 est in May and October and least in 

 July and August. Its distribution over 

 the island is determined by the prevail- 

 ing northeast trade wind and by the 

 local topography. At Port Antonio, 

 on the coast north of the Blue Moun- 

 tains, the total is 130 in., at Kingston, 

 on the coast south of the Blue Moun- 

 tains the annual total is 37 in. On the 

 summit of the Blue Mountains the total 

 is 168 in., an amount which is probably 



greatly exceeded at about 4000 to 5000 

 ft. on the north slopes of the Blue 

 Mountains. The rainfall for other lo- 

 calities in the island ranges from 30 

 to 100 in. 



VEGETATION 



The original vegetation of Jamaica 

 has long been destroyed in the plains 

 and valleys devoted to the cultivation 

 of sugar, bananas and coffee, but there 

 still remain in virgin condition extensive 

 areas of forest on the higher mountains 

 and on the relatively arid hills of the 

 south and southwest, as well as in the 

 Cockpit Country. There are also large 

 areas of swamp and savanna and smaller 

 ones of semi-desert that have not been 

 disturbed. Many of these areas which 

 are without economic value, but of the 

 greatest scientific interest, are held in 

 perpetuity as Crown Lands, which 

 assures their continuance in an undis- 

 turbed state. In the most frequented 

 portions of Jamaica the character of the 

 vegetation is largely determined by 

 introduced plants, such as the bamboo 

 and royal palm, the mango, tamarind 

 and breadfruit, the grass Arundo donax, 

 and the large leguminous tree Pitheco- 

 lobium saman. 



The vegetation of Jamaica may be 

 very roughly divided into lowland rain- 

 forest, montane rain-forest, lowland 

 monsoon-forest, savanna, semi-desert, 

 grass swamps and mangrove swamps. 



The lowland rain-forest covered the 

 northeastern corner of the island and 

 higher elevations and windward ex- 

 posures in the central parishes. What- 

 ever may have been the character of the 

 finest of the original rain-forests, there 

 exist today only suggestions of such 

 forests as may be seen in Vera Cruz or 

 Demarara. The height and density 

 of the canopy are seldom such as to 

 preclude a dense growth of subordinate 

 trees and shrubs, herbaceous plants, 

 lianes and epiphytes. There is, as usual, 

 a large number of species of trees, in- 

 cluding the silk cotton (Ceiba pentan- 

 ^ the Santa Maria tree (Calophyllum 



