26 
Origin of the British Flora. 
main directions in which British plants are specially adapted 
for dispersal are the following :— 
Modification. 
Abundance of minute seeds 
(Heaths, Rushes, Saxi- 
frages, Caryophyllacee, 
&c.). 
Abundance of large edible 
seeds (Oak, Pine, Horn- 
beam, Ivy, &c.). 
Edible fruits with hard 
stones (Blackberry, Haw- 
thorn, Holly, Arbutus, 
&c.). 
Winged seeds (many Com- 
posites, Willows, &c.). 
Winged seeds with lax 
hairs ( Willow - herbs, 
Willows, Bulrush, &c.). 
Burrs and hooked seeds. 
Floating seeds. 
Cut-leaved submerged water- 
plants ( Water - crowfoot, 
Water-milfoil, &c.). 
Mode of Dispersal. 
Readily moved by accidents 
of all sorts. 
Eaten or dropped by birds ; 
most are destroyed, but 
some are transported un- 
injured. 
Eaten by birds and mam- 
mals; seeds passed unin- 
jured. 
Transported by wind. 
Cling to feathers or fur. 
Transported by water. 
Collapse and cling when re- 
moved from the water; 
stems fragile, and broken 
pieces grow. Carried on 
legs of mammals or of 
wading birds. 
The first group, the minute-seeded plants, is a very 
large one, and it will readily be understood that the plants 
belonging to it include nearly all the British species which 
show strikingly anomalous distribution. 
Nearly all of our 
Alpine plants, of the Lusitanian species found in Ireland 
