NOUTHUMBEELAND AND DURHAM. 



303 



LIST OF BALLAST PLANTS. 



The following is a list of the more remarkable stranger-plants 

 which from time to time hare been gathered on the ballast-hills 

 of the two counties. Their localities are indicated by letters 

 placed in three columns, T. meaning the heaps on the banks of 

 the Tyne, S. those in the neighbourhood of Sunderland, and H. 

 those in the neighbourhood of Hartlepool and the Tees mouth. 

 The list is compiled from Winch's Flora and papers by the Rev. 

 A. M. ]S"orman and Mr. M. A. Lawson in the 5th vol. of our 

 Transactions, with a few additions from other sources. In the 

 countries mentioned in the second column the species are either 

 natives or well-established weeds. Those for which no letters 

 are given are mentioned in Winch's list without any particular 

 locality. We believe that it rarely happens that any of these 

 ballast introductions ripeu seed, and spring up a second time, so 

 that when fresh importations cease they disappear speedily. Al- 

 though we see that this ballast-list includes more than a hundred 

 and fifty species, of the plants mentioned in the body of the work 

 Reseda lutea, Sinapis tenuifolia, Pastinaca sativa, and perhaps 

 three or four of the Chenopodiacece are all that are at all likely 

 to have been introduced in this way. As Mr. Lawson has ex- 

 plained in his paper, for the first year or two after the ballast 

 has been laid down the annuals spring up ; then these disappear 

 and the perennials succeed them ; and, finally, in the struggle for 

 existence, if the heaps become disused, these are crowded out by 

 thistles and wormwood, milfoil and ragwort, Triticum, and Am- 

 mophila, and Festuca rubra. 



Clematis vitall>a, L 



Ranunculus hirsutus, Cvrl 

 muricatus, L. 



Delphinium Ajacis, L 



Nigella an'ensis, i 



damascena, L 



Papaver hybridum, L 



Argemone mexicana, L. . 



S. England 

 England ... 

 S. Europe 

 S. Europe 

 S. Europe 

 S. Europe 

 England ... 

 Mexico . . . 



