WEST INDIAN LAND PLANTS AND ANIMALS. 349 



Land Flora and Fauna. 



The land floras and faunas of the Great and Lesser Antilles are of extreme 

 interest to naturalists, owing to the endless contrasts and resemblances that they 

 present from island to island, and to the means thus offered of determining the 

 original continuity or geological independence of the several groups. The great 

 diversity of forms in the different islands has been regarded as a proof of long 

 isolation. Each island has forms peculiar to itself, and if the various types from 

 the mainland speak of communications through isthmuses at remote epochs, it is 

 evident that such migrations must date from pre-tertiary times, and that the 

 postulated West Indian isthmus, if it ever directly connected the northern and 

 southern continents, has ceased for many ages to offer a free passage to plants 

 and animals. 



The special faunas are most pronounced in the land shells, the Antilles occupy- 

 ing in this respect a unique position. For these organisms each island may be 

 said to constitute an independent centre of evolution. Nevertheless, the Great 

 Antilles as far as the Virgin group must at some remote epoch have been 

 attached to Mexico, the Lesser Antilles on the one hand to Venezuela, on the 

 other to the Guianas. 



The birds, -which, for the most part, easily cross intervening straits, have 

 spread from island to island over vast spaces. Certain species have even been 

 wafted by hurj-icanes across broad marine channels ; the pelican appears to have 

 been first introduced into Guadeloupe in this way in the year 1685. 



The AVest Indies possess fifteen distinct species of the humming-bird, grouped 

 in eiglit genera, of which five are unknown on the neighbouring mainland. On 

 the whole the avifauna seems more related to that of the southern than of the 

 northern continent, while the reptile order has greater affinities with those of 

 Central America and Mexico. But some remarkable instances of specialisation 

 have been observed ; such are an iguana peculiar to Haiti and the islet of Navaza, 

 and a trigonocephalus confined to St. Lucia, St. Vincent, and Martinique. The 

 Cuban ant-eaters belong to a group found elsewhere only in Madagascar. 



In general the insular faunas and floras belong to the same zone as South 

 Florida as far as the marshy everglades, but have little afiinity with those of 

 the L^nited States proper. Analogies occur most frequently with Mexico, Honduras 

 and the other Central American regions. The deep-sea fauna, also, is more akin 

 to that of the Pacific than of the Atlantic Ocean, proving that before the chalk 

 period the Central American isthmuses formed a chain of islands with broad 

 intervening marine channels. 



The term Antilles, applied to the West Indian insular world, dates from a 

 period anterior to the discovery itself. Antilia was one of the islands of the 

 Gloomy Ocean, figuring on the maps at one time as an archipelago, at another 

 as continuous land and wandering up and down the seas between the Canaries and 

 East India. With the progress of discovery Antilia continually retreated more 

 towards the setting sun, until it was at last identified with the " West Indies " 

 discovered by Columbus. 



