1905-1906.] Formation and Flora of a Shingle Island. 3 ( i 



In column 1, "x?" indicates that the wind may have 

 played a subordinate, but probably not an important, part, in 

 that particular case. In column 2 we have included those 

 species that were obviously carried down by the stream, and 

 also those that were growing on the river-bank or the wooded 

 island above, and seemed to have some chance of dispersal by 

 the river. Column 3 shows those plants which are growing 

 profusely in the neighbourhood. Column 4 indicates our 

 opinion that the plants therein may reach the island through 

 the small dispersals of seed year by year, without special 

 assistance from wind or water, — in fact, by a kind of 

 " marching." By " x X " in any of these columns we mean 

 that we have reason to think the factor in question a specially 

 important one ; and this mark has only been put after careful 

 consideration of the distances involved, and the lie of the land, 

 in each case. Columns 5 and 6 deal with advantages of 

 environment ; and 7 and 8 with advantages inherent in the 

 plant itself. Thus column 5 shows in what particular the 

 island soil is suited to the plant, " s " meaning that the plant 

 in question is known to thrive in sandy soil ; " st," that it 

 thrives in stony places ; and " w," that it thrives in waste 

 places.^ Column 6 shows the plants that like moisture ; " d " 

 meaning that they usually grow in a damp situation, and " r " 

 that they grow in a riparian situation. (The island would 

 seem rather a dry place, but its closeness to water, and the 

 frequent floods, presumably supply enough moisture to answer 

 to the requirements of these plants.) Column 7 explains 

 itself.^ We shall discuss, later on, the advantage of the 

 " creeping root " indicated in column 8. 



Taking now the "qualifications for reaching the island," 

 and analysing the figures, our results may be shown briefly in 

 the table on next page. 



^ For lists of plants growing in sandy places we are indebted to the ' Botanical 

 Survey of Scotland,' Part II., by Robert Smith, B.Sc, and Part III., by Wm. G. 

 Smith, B.Sc. 



2 We have decided as to the "adaptability" of a plant by noting the variety of 

 habitats in which it occurs ; this information being drawn partly from our own 

 notes and partly from lists in the ' Botanical Survey of Scotland.' 



