176 PLANT DISTEIBTJTION. 



eventuate in a fairly general interchange of flora. This sort of 

 thing has been going on ever since primitive man first left his 

 native shore in his frail coracle. At present, due to the intro- 

 duction of seed with ballast and merchandise, our busiest sea-ports 

 have the richest floras. Within recent years the ballast heaps 

 around Cardiff — by no means the most important town one might 

 mention — have produced plants from almost every land under the 

 sun. Even the flora of inland towns is yearly enriched by the 

 seeds which come from other lands as stowaways, in bales, 

 packages, &c. Finally, not to enlarge on a very interesting 

 subject, it has been remarked that whenever a country has been 

 invaded by a foreign army a distinctively new flora has followed 

 in its trail.* 



Coincident with this — if the phrase may be permitted — 

 international exchange of plants, a local re-distribution, is also 

 going on. Within recent years the flora of the Kennall Valley 

 and neighbourhood has thus been enriched by twenty-one 

 wanderers, of which thirteen have become permanent additions. 

 Eor the sake of distinctness the two classes will be kept separate, 

 and those which have become naturalised will be treated first. 



Linaria repens is a notable example. For many years this 

 elegant little toad-flax was confined to the south portion of Mabe, 

 but by yearly increments it pushed its way northward until 

 about twelve years ago it reached the turnpike road from Penryn 

 to Helston. Then in the year 1885 it appeared in profusion on 

 a newly-built hedge near Devas Farm, having taken a sudden 

 leap of over two miles. At about the same time several plants 



* " The year after Thorwaldsen's sculptures had been unpacked in 

 Copenhagen, twenty-five plants of the Roman Campagna sprang up in the court- 

 yard of the Museum, the seeds having, of course, been introduced in the hay, 

 straw, &c. , which had accompanied the works of art from Rome. In the campaign 

 of 1814, the Russian troops brought in the stuffing of their saddles seeds from the 

 banks of the Dneiper and the Don to the valley of the Rhone, and even introduced 

 the plants of the Steppes into the environs of Paris. The Turkish army, in its 

 European incursions, left the seeds of Eastern plants to bloom on the ramparts of 

 Buda and Vienna. The Walcheren expedition of 1809 brought Lepidium Draba 



to the Isle of Thanet, where for long it was a most troublesome weed 



Since the Franco German war, the seeds of numerous Algerian plants have 

 naturalised themselves on the camping grounds of troops brought from the 

 African colonies, or where forage from the shores of the Mediterranean had 

 been used." — Dr. Robert Brown, F.L.S., in Science for AU,Yol. iv., p. 6. 



