452 MEXICO, CENTEAL AMERICA, WEST INDIES. 



being derived from the disintegration of the surrounding rocks. It is composed 

 of substances found in the calcareous sands, and left as a residuum after repeated 

 rain washings. It thus belongs to the same class of fertile soils which are also 

 met in Cuba and other islands of coralline origin. The reddish clays forming 

 the marine bed in depths of over 2,000 fathoms, are similarly derived from the 

 remains of foraminiferse, showered down in countless myriads from the surface of 

 the sea, and dissolved by the salt waters during their descent. 



The porous nature of the ground facilitates the formation of this red earth, 

 which is continually dissolved by the rains percolating freely through the rocks. 

 Hence the surface waters nowhere develop streams, though they are here and there 

 collected in cavities near the shore. " Tidal wells," as in the Bahamas, supply 

 drinking-water ; but the rainfall itself is sufficiently copious to enable the inha- 

 bitants to depend on the cistern erected at the side of every dwelling. 



Climate. 



Thanks to the Gulf Stream and aerial current setting in the same direction, 

 the climate of the Bermudas is warmer than might be expected from their latitude. 

 The mean temperature is about 70° Fahr., or nearly four degrees higher than that 

 of Madeira, which lies under the same parallel. Between the coldest and hottest 

 months (February and June) the range is 27°, G0° and 87° Fuhr. respectively 

 Thus, despite the tropical character of the climate, the alternation of the seasons 

 is well marked, being the result of the play of the shifting polar and equatorial 

 winds. It is probably to this periodical change, better regulated and extending 

 over a wider range than in Madeira, that the English residents in Bermuda are 

 indebted for their general good health ; the average mortality amongst them is 

 23 per thousand, or about exactly the same as in England Tropical disorders 

 are rare, although in 1856 the white population was decimated by an outburst 

 of yellow fever introduced from the Virginian coastlands. 



Like most oceanic islands, the Bermudas, despite their distance from the main- 

 land, do not constitute a distinct vegetable centre. The spontaneous flora, apart 

 from that introduced by man, consists exclusively of species brought either by 

 the Gulf Stream or by the south-west trade winds. Seen from the summits of the 

 eminences, the island^s appear to be almost completely clad with a dark mantle 

 of "cedars" (Junipenis ba rbadensis), irora the Lesser Antilles ; they are always 

 associated with a verbena (h)ifana odorata), also from the Antilles, which has 

 driven out the native grasses. The rocks, being destitute of vegetable humus, are 

 clothed with the stcnotiqyhruin ameviranum, a herbaceous plant from the Bahamas. 



As in Cuba and Mexico, the shores are fringed with mangroves ; but the only 

 member of the palm family which grows freely is the palmetto sahal of Florida. 

 All the other palms are exotics, even the magnificent oreodoxa, which lines certain 

 avenues about the capital, and which the Bermudans are proud to show to visitors. 

 Both the date and cocoanut palms are grown, though the fruit seldom ripens. 

 Altogether, the vegetation, springing from a porous limestone soil, where ths 



