304 M. A. LAWSON, B.A., ON THE FLORA OF THE 
XXXIX.—WNotes on the Flora of the Old and West Hartlepool 
Ballast Hills, with alist of the rarer and more characteristic 
species. By M. A. Lawson, B.A., Trin. Coll., Cam. 
Tue list which accompanies this paper contains only the more 
rare or characteristic plants which I have found on the two 
Hartlepool Ballast Hills. 
It extends over a period of about seven years, when I first 
began to pay attention to the subject. For long I was foolish 
enough to throw away any plant I could not at the time make 
satisfactorily out. Otherwise I believe my list would have con- 
tained a larger number of foreign species than it does at present. 
For a long time I have observed that after the ballast is first 
thrown out, it is covered almost solely with Annuals, but in two 
or three years these Annuals have either entirely disappeared, or 
else, from their scarceness, have become a very inconspicuous part 
of the flora, and a vast variety of Perennials have sprang up 
in their place, which in their turn overrun the whole ground, 
and then gradually dwindle away to a most minute fraction of 
their former abundance, so that even if there were no spot from 
which they had entirely disappeared, it might be reasonably sup- 
posed that they would in afew years, at the furthest, become 
extinct. 
Now, at the extreme South end of the Old Hartlepool Ballast, 
there are several such spots utterly destitute of Perennials, with- 
out even, I believe, a patriarchal ‘ Diplotaxis tenuifolia,” or 
‘“¢ Reseda lutea.” 
On these spots there are no bents and very little sand; but 
there is—and this seems eventually to get the better of everything, 
—a thick covering of short coarse grass, with a sprinkling of 
“yaowort,” “yarrow,” and ‘ Carduus nutans.” But it is not 
only on these few isolated spots that this is observable, for the 
same is evident on a regularly graduated scale from the compara- 
tively new ballast to these bare spots,—the grass gets thicker, and 
the perennial shrubs more scraggy. 
This, I think I may safely say, is observable on the whole of 
the Old Hartlepool Ballast Hills, but a part of West Hartlepool 
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