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There are good reasons for this exceeding richness of the fern 

 flora in Jamaica. The island lies between 17 43 and 18° 32' 

 north latitude, the northern limit being more than five d-grees 

 south of the Tropic of Cancer, and the southern shore more than 

 six degrees south of the same Tropic. The Blue mountain range 

 in the eastern extremity of the island rises from 6.000 to 7.000 ft. 

 above sea level, and Blue Mt. peak towers to the height of 7,360 

 ft., or nearly a mile and a half perpendicular in the air. The 

 southern shore of the island, besides lying fifty miles farther 

 south than the northern, is sheltered by these lofty ranges of 

 mountains from cooler breezes, and at some points is said to be as 

 torrid in climate as Barbadoes or Trinidad. In fact, Kingston, 

 the capital, has the reputation of being one of the hottest places 

 in the West Indies. Thus the climate ranges from the extreme 

 heat of the tropics on the southern shore, to the cool temperature 

 of the northern temperate zone on the mountain tops ; while the 

 various gradations between these are found as one travels from 

 the level of the coast to the higher altitudes of the mountains. 

 In addition to this variation in temperature, there is a great va- 

 riation in moisture. On the Liguanea plain, which extends six 

 or seven miles inland from Kingston and is somewhere near four- 

 teen miles long from east to west, rain does not fall more than 

 two or three times during the six months of the dry season ; but 

 the mountains are famous for attracting thre clouds, so that rain 

 falls there all the year around and nearly every day, often in 

 deluges of water. Moisture and heat therefore, which are prime 

 requisites for the growth of ferns, are here in abundance ; while 

 on the mountain summits a much colder temperature prevails, 

 and gives a wonderful variety to the climate. This is evidenced 

 by the fact that Cystopteris fragilis, which is a cold temperate 

 species, and has even been found as far north as Iceland, and 

 Dryopteris filix mas, which grows throughout northern Europe, 

 in Greenland, and at an elevation of 15.000 ft. in the Himalayas, 

 have recently been discovered on Blue Mt. peak, the only known 

 habitat of these species in the West Indies. 



The Blue mountains proper is the place to see the tTee ferns 

 growing in perfection. Jenman states that the trees of Cyathea 

 arborea form unmixed groves, "while the stems constitute the 

 only wood used or easily procurable in certain districts as posts 

 in the houses of the peasantry." This species reaches the height 

 of thirty feet; while C. pubescens often attains a height of forty 

 feet. The tallest fern of the island, however, is Alsophila armata, 



