306 M. A. LAWSON, B.A., ON THE FLORA OF THE 
The great difficulty in naming Ballast Hill plants arises from 
two causes, the first of which is the great deformities and mons- 
trosities that are met with, naturally attendant upon great change 
of temperature or unusual dryness. The second cause arises from 
the impossibility of forming any idea from what part of the 
world the plants have come, and consequently the difficulty in 
referring them to their proper books. ‘There might be growing 
side by side ‘‘ Centaurea Orientalis,”’ from Odessa, and ‘“ Sinapis 
Monensis,” from the west coast of our own country, and no clue 
whatever to distinguish their native localities. 
The periods to which the figures 1, 2,38, relate, are those 
after the ballast is thrown out, in which the species seems to have 
come to, or have passed its most luxuriant stage. Asa general rule 
the Ballast Hills during the first three years are, for the most part, 
covered with Annuals. This I call the 1st or period of Annuals. 
The 2nd, that of Perennials, extends from the end of the third 
year to the end of the tenth. After which comes the 3rd or Con- 
stant period, when coarse grass, ragwort, and yarrow, hold the 
ground undisturbed by any succeeding set of plants. When more 
than one number is affixed, the plant is observed to flourish 
during the end of one period, and the beginning of the next. 
One large patch on the railway 
embankment by the second arch 
north of Hartlepool. 
23 Clematis vitalba 
1 Delphinium consolida One fine plant, Old Hartlepool 1858. 
1 Papaver hybridum Old Hartlepool. 
1 argemone Old and West Hartlepool. 
1 somniferum Old and West Hartlepool, occa- 
sional plants, one this year. 
2 Glaucium luteum Old Hartlepool, common. 
2 Nasturtium amphibium Old Hartlepool, occasional plants. 
2 palustre Old Hartlepool, common. 
2 sylvestre Old and West Hartlepool, common. 
1 Sisymbrium Irio Old Hartlepool, rare. 
sophia Old and West Hartlepool, common. 
1 Erysimum cheiranthoides Old Hartlepool, very rare, 
12 Brassica oleracea 
1 Sinapis monensis 
Old Hartlepool, once very common. 
Old Hartlepool, rare. 
