96 Brenchley.—The Weeds of Arable Land in 
each seen once or twice only. As in the previous investigation, attention 
was confined to those weeds growing in among the crop, the weeds of the 
surrounding hedgerows being left out of consideration. The classification 
of the soils did not present so much difficulty as in the case of the Bedford- 
shire work. The areas dealt with were much larger, and adjoining fields 
did not show the sudden change in the nature of the soil that occurred so 
frequently in the eastern county. In the chalk areas rather more sub- 
division had to be made this year. The presence or absence of lime in the 
various soils was frequently tested for with dilute hydrochloric acid. 
The seasons in the two years of investigation were of totally different 
character, that of 1910 being wet and cold, with a deficiency of sunshine, 
while that of 1911 was characterized by an excessive amount of sunshine 
and by high temperatures, coupled with a low rainfall, so that conditions of 
drought prevailed. This radical difference may have influenced the relative 
occurrence of certain species, so that it is quite probable that some of the 
diversity in results may be due to seasonal variation rather than to the 
actual differences in the nature of the soil. 
The chief species of weeds, with their habitats and dominance, were as 
follows : — 
Ranunculaceae. Ranunculus acris. Found on clay and sand. Absent 
from chalk. Never dominant. 
Ranunculus arvensis. Chiefly found on clay, once on chalk. Never 
dominant. (Rarely seen in this district ; far less frequent than in 
Bedfordshire.) 
Ranunculus repens . Most frequent on chalky soils ; also seen on clay 
containing a fair proportion of lime. (N.B. — It is possible that in the 
Bedfordshire districts R. repens occurred in some instances, but was not 
separated from R. acris.) Never dominant. 
Papaveraceae. Papaver hybridum . Only occasionally seen, then on 
chalky soil. Never dominant. 
Papaver Rkoeas. Characteristic of chalky soils ; hardly seen elsewhere. 
Occasionally dominant. (Many observations of poppies were made when 
the plants were too small to permit the species to be identified. These 
usually occurred on chalky soils, with one record (dominant) from sand.) 
Fumariaceae. Fumaria officinalis . Chiefly on chalky soils, but fairly 
frequent on loam. Several records from clay, but then it was usually 
occasional or scarce in distribution. Occasionally dominant on chalk or 
loam. 
Cruciferae. Brassica alba. Practically confined to chalk and brashy 
loam (limestone). Frequently dominant ; one instance of dominance on 
clay, which proved to contain much limestone. 
Brassica S inapis. Chiefly on chalk and red land ; also much on clay 
