INDIVIDUAL SPECIES. 19 
considerably both on Area 6 and on Area 7 under the influence 
of heavy sheep grazing and (or) drought in 1918. 
The results for all these areas taken together suggest that the 
grass has held its own better on the lighter and drier soil (Areas 
6 and 7), and there is some indication also that there may bea 
distinct relationship between the amount of seed sown and the 
P.c. fr. of the grass for some years where the other conditions are 
fairly equal. There is a suggestion, however, that in some cases 
at least, thorough cleaning of the land is advantageous to the grass 
(Area 3), although on Area 7 it was by far the most successful 
sown grass. 
Festuca elatior et var. pratensis. 
These grasses were only recorded on one of the grazed 
pastures examined by Armstrong, and.on this they formed 1 per 
cent. of the herbage (1). 
On the best pasture examined by the writer, they had a 
P.c. fr. of 6, but they have not been recorded on any of the other 
old pastures examined. Their presence to the extent of 6 per 
cent. on the pasture referred to may not mean that they were 
indigenous. The pasture was but 18 years old, and they may 
have persisted from sowing. It is more probable, however, that 
their presence was due to the fact that cattle are regularly winter- 
fed on the field, and the seed might be repeatedly introduced in 
the hay. That this is at least possible is shown by the fact that 
although the grasses are completely exotic to Areas 1-8 and even 
to the district, they appeared in small quantity on a permanent 
hay meadow on the farm in a few years after the seed had first 
been sown on Area 2. 
Only a very small quantity of seed was sown as an experi- 
ment on Area 2, but the grasses were recorded at each examination 
up to 9# years. 
On Area 3 a heavier seeding was given, and although the 
P.c. fr. was low at 44 years, it was slightly higher than that given 
by a heavier seeding of Pileum pratense (Table IV., p. 16a), and 
in the following year the difference was still greater as the Festuca 
spp. had increased while Phlewm pratense had decreased, 
