July, 1836. 



CHANGES IN VEGETATION. 



583 



the old ones, which were safe from their attacks, perished 

 from age, seems clearly made out. Goats were introduced 

 in the year 1502 ; eighty-six years afterwards, in the time 

 of Cavendish, it is known they were exceedingly numerous. 

 More than a century afterwards, in 1731, when the evil was 

 completed and found irretrievable, an order was issued that 

 all stray animals should be destroyed. 



When at Valparaiso, I heard it positively affirmed, that 

 the Sandal-wood tree had been found on the island of Juan 

 Fernandez in considerable numbers, but that all without ex- 

 ception were standing dead. At the time, I thought it was 

 some mysterious case of the natural death of a species ; but 

 when it is remembered, that goats for very many years have 

 abounded on that island, it seems most probable that the 

 young trees were prevented growing, and that the old ones 

 perished from age. It is a very interesting fact, to observe 

 that the arrival of animals at St. Helena in 1501 did not 

 change the whole aspect of the island, until a period of two 

 hundred and twenty years had elapsed : for they were intro- 

 duced in 1502, and in 1/24 it is said "the old trees had 

 mostly fallen .^^ There can be no doubt, this change affected 

 not only the Bulimus and probably some other land shells (of 

 which I obtained specimens from the same bed), but likewise 

 a multitude of insects. 



St. Helena, situated so remote from any continent, in the 

 midst of a great ocean, and possessing a unique Flora, — this 

 little world within itself, — excites our curiosity. Birds and 

 insects,* as might have been expected, are very few in number ; 



* Among these few insects, I was surprised to find a small Aphodius 

 (^nov. spec.) and an Oryctes, both extremely common under dung. When 

 the island was discovered it certainly possessed no quadruped, excepting 

 perhaps a mouse ; it becomes, therefore, a difficult point to ascertain, 

 whether these stercovorous insects have since been imported by accident, 

 or if aborigines, on what food they formerly subsisted. On the banks of 

 the Plata, where, from the vast number of cattle and horses, the fine 

 plains of turf are richly manured, it is vain to seek the many kinds of 

 dung-feeding beetles, which occur so abundantly in Europe. I observed 

 only an Oryctes (the insects of this genus in Europe generally feed 



