SHORE AND SALT-MARSH 333 



copied by the black-headed gulls. But some of the black- 

 headed gulls have improved upon it ; we have watched them 

 swimming a little further out in the shallows, paddling with 

 their dropped feet, and catching the food disturbed in the 

 water around them. In a flock of scores of birds only half 

 a dozen may be seen beating out their food in this way, 

 while the others hunt for what is already exposed ; and the 

 plan is much more common among herring-gulls than black- 

 headed gulls. Thrushes will sometimes catch worms in the 

 same way on a lawn, and marine worms of different species 

 form probably the bulk of the prey secured by the gulls in 

 beating both above and below the water. But gulls are 

 largely garbage feeders, which is one reason why they thrive 

 as parasites of man about fishing-ports and on the refuse 

 heaps outside towns. They pick all kinds of animal re- 

 fuse washed up along high-water mark, from dead birds and 

 fish to bacon rind thrown from the galleys of passing coal 

 tramps. 



A curious vegetable waif of sandy and gravelly shores 

 is the tea-plant, which grows in hedges and low thickets, and 

 is a straggling bush in no way related to the shrub which 

 gives us tea. It is a member of the solanum tribe, which has 

 a rare faculty of getting about the world by human aid, as 

 is shown by the potato and the thorn-apple. The tea-plant 

 has oval pointed leaves something like those of the real tea- 

 shrub, and seems originally to have been named by some 

 confusion. It has pale purple blossoms sufficiently like those 

 of the woody nightshade to suggest their relationship, and is 

 conspicuous among the seaside flora when in bloom. Green 

 hairy tamarisks with their spraylike plumes of pink blossom 

 are also prominent on the outskirts of seaside towns and 

 gardens, but they have never freely established themselves 

 as wild plants. Sea- buckthorn and the shrubby sea-blite 



