PROCEEDINGS-PERTHSHIRE SOCIETY OF NATURAL SCIENCE. CV 
3. Probably Introduced. 
Regarding the intentional or accidental introduction into Perth¬ 
shire, if not into Britain, at a remote period, of several of the species 
in this group there can be no doubt. As regards others there is 
more uncertainty, and possibly they ought to be placed in a higher 
group. Still, from the circumstances under which they occur, their 
proper position seems to be here. 
Barbarea vulgaris. 
Arabis perfoliata. 
Sedum Telephium. 
Conium maculatum. 
AEgopodium Podagraria. 
Myrrhis Odorata. 
Anthriscus vulgaris. 
Artemisia vulgaris. 
Symphytum tuberosum. 
Mentha sylvestris. 
U9) 
Urtica urens. 
,, dioica. 
Allium Scorodoprasum. 
,, carinatum. 
Bromus sterilis. 
„ racemosus. 
Trisetum flavescens. 
Poa compressa. 
Lolium perenne. 
4. Roadside and Hedgebank Plants. 
There are a few species which are so restricted in their distri¬ 
bution to roadsides and hedgebanks that it is impossible to avoid 
the conclusion that they are now, at least, dependent on the opera¬ 
tions of man for their existence as constituents of the flora. They 
can scarcely be classed as colonists, since they are not, in a strict 
sense, plants of cultivated ground. More likely they are old intro¬ 
ductions, but neither is this certain. It is possible, though perhaps 
not probable, that they may be really natives which have been driven 
to the place where they now exist, and have adapted themselves to 
live there. Several of the colonists and some of the probably intro¬ 
duced plants are also roadside and hedgebank species, but the 
following six are specially such. (6) 
Sisymbrium Alliaria. 
,, officinale. 
Lychnis alba. 
Chaerophyllum temulum. 
Caucalis Anthriscus. 
Lamium album. 
5. Colonists. 
Watson defines a “colonist” as a species “found only in ground 
adapted by man for its growth and continuous maintenance.” Now, 
whilst there are a considerable number of plants which occur only 
in cultivated ground, there are others which, although most common 
in such ground, are not altogether restricted to it. Those which are 
confined to cultivated ground have their' nature well expressed by 
the term “weeds of cultivation.” While some of them have been 
certainly introduced with the seeds of cultivated plants, it is not 
impossible that others have existed from the time when the surface 
of the country was less clothed with vegetation, and have been 
driven to the cultivated land because they find there the conditions 
necessary for their growth. Some other species have been included 
in the list of colonists because, though they are not restricted to 
cultivated ground, they are much more abundant there than else- 
