102 
WARWICKSHIRE STOUR VALLEY AND ITS FLORA. 
or by roadsides, and seldom found except where cultivation 
exists;” as Ranunculus arvensis, Alopecurus agrestis. “ Alien 
species are those plants certainly or very probably of foreign 
origin ; ” as Acer Pseudo-platanns, Sedum. rejicxum. “ Casual 
species are chance stragglers from cultivation, such as are 
found on waste heaps, railway embankments, and sometimes 
in cultivated fields ; ” as Trifolium hybridum , Medico go sativa. 
The 683 plants found in this valley are made up as 
follows:— 
Natives ... 
... 502 
Denizens 
12 
Colonists 
... 26 
Aliens 
13 
Casuals ... 
5 
Varieties 
... 80 
Species not classified by Watson 
45 
683 
The twelve Denizens are Chelidonium magus, Hesperis 
matronalis, Geranium pyrenaicum, Meiilotus officinalis, Sedum 
refiexumAEgopodium Podagraria, Sambucus Ebulus, Matricaria 
Parthenium, Vinca minor, Chenopodium Bonus-Henricus , Ulmus 
suberosa, U. montana. 
Aliens.—Cheirantlius Cheiri, Corydalis lutea, Cochlear ia 
Armoracia, Dianthus Armeria, Acer Pseudo-platanus, Medicago 
sativa, Ribes nigrum, Sedum album , Linaria Cymbalaria, Populus 
alba , P. nigra , laxus baccata, Elodea Canadensis. 
Casuals.—Brassica Rutabaga, Stellaria nemorum, Meiilotus 
arvensis, Trifolium hybridum, Vicia sativa. 
The species not classified by Watson are the segregate 
species of Batrachian Ranunculi, and of the genera Rubus , Rosa, 
Salix, dc., placed under a separate number in the 8th edition 
of “ The London Catalogue of British Plants.” 
Types of Distribution .—In making out the types of distri¬ 
bution of the plants found in the Stour Valley I have again 
had recourse to Mr. Watson’s valuable work, in which he gives 
six leading types of distribution, which may be briefly shown 
thus:— 
1. —British Type.—Species widely spread through South, 
Middle, and North Britain. 
2. —English Type.—Species chiefly seen in S. or S.-M. 
Britain. 
3. —Scottish Type.—Species chiefly seen in N. or N.-M. 
Britain. 
