INDIVIDUAL SPECIES. 47 
1-4 it was much more widely distributed, and had a much higher 
P.c. fr. up to 54 years than later. Different from species already 
mentioned, this plant decreased very rapidly in most cases, so that 
on Area 2 its Sp. fr. had decreased from 67 at 5} years to 4 at 84 
years. Its Sp. fr. on Area 5 at 104 years was relatively very high 
as compared with the other areas. This may be due to the 
slightly lighter soil. 
Sagina procumbens. 
Owing to the habit of this plant, it is not easy to detect it 
where the turf is fairly thick and the plants small, so that the 
P.c, fr. results may be more reliable than those obtained by the 
Sp. fr. method. 
The highest P.c. fr. was obtained on Area 2 at 7} years, and 
apparently, on Areas 1-5 it reached its maximum at about this 
time, and then decreased fairly rapidly. 
It was not recorded on Area 8, and on Areas 6 and 7 it was 
but poorly represented except on Area 6 at 64 years. In respect 
of this plant Area 6 appeared to be reverting to the heath con- 
dition more rapidly than Area 7. 
Luzula campestris. 
Few records were obtained for this plant by the Sp. fr. 
method. Its highest P.c. fr. was obtained on Area 8 (grass- 
heath), but as compared with other areas, especially Area 6, at the 
corresponding periods, it was well represented on Area 7 both at 
54 and 64 years. Only traces were recorded on Area 6, so that 
in respect of this plant Area 7 was reverting to heath condition 
most rapidly. 
The plant was not recorded on Area 1 at 44 years nor on 
Area 3 at 84 years, andit -was but poorly represented on these 
areas a year later in each case. 
The results for the other areas seem to show that on 
this land it tends to increase with the increasing age of the 
pasture, although its P.c. fr. was lower at 104 years than at of} 
1Qn old pastures examined by the writer, its highest P.c. fr. was 1°3 on 
a soil inclined to be gravelly or sandy (College Farm, Bangor). 
