418 CAMP-FOLLOWERS OF COMMERCE, OR 



nearest land, was discovered in 1501, it was described as 

 possessing about 60 species of plants, all of which, with very 

 few exceptions, were unique. But before the days of the 

 Suez Canal, St Helena lay on the great ocean highway 

 from Europe to the East. The result of constant traffic is 

 clearly perceptible in the change which took place in its 

 flora; for in less than two and a half centuries, a little design 

 and much accident had brought its plant species up to the 

 number of seven hundred and fifty. So also the settlers 

 who formed the first British colony in New England were 

 astonished to find weed after weed, known to them in the 

 old country, spring up in the neighbourhood of their new 

 cultivation, until they had more than thirty familiar weeds 

 they had thought (and had hoped) to have looked on for the 

 last time on the other side of the Atlantic. 



How do these unsought aliens find their way across land 

 and sea? They seem to utilize any means of transport that 

 man has devised for his own furtherance, concealed often 

 in curious corners and crannies until they are dumped in the 

 fertile soil of a new country. Napoleon's troops on their 

 return to France from the Russian campaign of 18 14 brought, 

 in the stuffing of their saddles, in fodder and in other un- 

 suspected ways, seeds of plants which had bloomed on the 

 banks of the Dnieper and deposited them in the valley of 

 the Rhine; they even introduced the plants of the steppes 

 to the heart of France. In similar ways, many plants from 

 Algeria and other countries entered France with the fodder 

 imported during the Franco-German war of 1870, and suc- 

 cessfully established themselves. 



Animals are more alive than plants, and while their 

 passive stages resting spores, full-fed larvae, pupae or 

 hibernating individuals may be transferred from one coun- 

 try to another almost with the ease of insensate seeds, they 

 themselves are also liable to be carried unintentionally, since 

 many find concealment amongst stores and material for 

 transportation. 



Regarding the general effects in a native fauna of these in- 

 vading animal stowaways, there is little to be added to the dis- 

 cussion of the effects due to deliberate introductions by man, 

 outlined in another place (p. 243): for both deliberate and 

 accidental introductions give rise to the same new com- 



