303 MEETING OF THE BRITISH ASSOCIATION. 
plantations. The only method adopted for tlie destruction of the 
voles is that of digging pits wider at the bottom than at the mouth, 
into which many fall, and are there killed or allowed to die. The 
number thus destroyed have, however, no sensible effect in lessening 
the swarms. There can be little or no doubt that the enormous in- 
crease is owing mainly to the relentless extirpation of rapacious birds 
and weasels, which are the natural police of the forests to maintain a 
balance of power. While nature gave unlimited fertility to the 
rodents, she bounded their destructive increase by the carnivores, and 
it is not wise for man, for the sake of amusement, to disturb that 
order. Nature will not suffer him with impunity to sacrifice her off- 
spring for game. Judgment will be upon him, — the forests become 
blighted, the land overrun with vermin, and he repents of the injury 
that he has done to the hawks, the owls, and the weasels. 
Professor Dickson exhibited an abnormal leaf of Primus Lauro- 
cerasm. 
The following papers bearing on botanical subjects were also read to 
the Association : 
Dr. Maxwell T. Masters.— On Polliniferous Ovules in a Rose (Rosa 
arvensis). This will be published in extenso in our next, with an illus- 
tration. 
Dr. Lauder Lindsay. — On the present uses of Lichens as dye studs. 
Dr. Lauder Lindsay. — Is Lichen-growth any criterion of the age ot 
prehistoric structures ? 
Dr. Lauder Lindsay.- Is Lichen-growth detrimental to Forest and 
Fruit Trees ? 
Dr. Lauder Lindsay.— On Plant Acclimatization in Scotland, with 
special reference to Tussac Grass. 
Dr. Lauder Lindsay.— On the Conservation of Forests in our 
Colonies. 
& J. Lowe.— On the Abnormal Forms of Ferns. 
Dr. Fraser.— On the occurrence of a new British Moss in Dovedale. 
Professor Balfour.— -Notice of some rare Plants recently collects 
in Scotland. — He noticed specially, Apera interrupta, Beam'., i° 
Dirleton Common, near Edinburgh ; Phyllodoce carulea, Bab., from 
the Sow of Athole, Perthshire; Polypodium alpestre, Hoppe, and • 
flexile, Moore, from Ben Aulder ; and an apparently undescribnl C« ra 
from the Sow of Athole. 
