12 



made before the advent of modern organic chemistry. Pharma- 

 cologists have already adopted newer methods and we are now doing 

 so for farm crops. During the past two years Messrs. Davis and 

 Daish, assisted by Mr. Sawyer, have worked out a satisfactory 

 method, of which details are given below, for estimating cane 

 sugar, dextrose, laevulose, and maltose in plants. A further method 

 is now being elaborated for determining the amount of starch ; this 

 is based on the fact that Taka diastase hydrolyses starch completely 

 to maltose and dextrose, no dextrin being formed. 



The following papers have been published during the year : — 



I. "The Weeds of Arable Land." III. WINIFRED E. 



Brenchley. Annals of Botany, 1913. 27, 141 — 266. 



In previous seasons the investigation had been confined to 

 sedentary soils; this year (1912), however, the records were taken 

 on the drift soils of Norfolk. The general results, however, are 

 closely in agreement with those obtained before, but the Norfolk 

 weed flora agrees more closely with that of Bedfordshire than with 

 that of the West Country. As before, the association between weeds 

 and soil is sometimes general, sometimes only local, but the follow- 

 ing weeds were characteristic of the soils examined this year : — 

 Clay & Heavy Loam. Loams. 



Alopecurus myosuroides Anthemis Cotula 



Geranium dissectum Bellis perennis 



Heracleum Sphondylium Brassica alba 



Linaria Elatine Chrysanthemum leucanthemum 



Potentilla reptans Euphorbia Peplus 



Ranunculus arvensis Lolium perenne 



Stachys palustris Lychnis dioica 



Papaver Argemone 

 Sand cS: Sandy Loams. Sands. 



Chrysanthemum segetum Bromus mollis 



Rumex Acetosella Echium vulgare 



Scleranthus annuus Erophila verna 



Spergula arvensis Lycopsis arvensis 



Myosotis collina 

 Chalk. 

 Artemisia vulgaris Euphorbia Helioscopia 



Cichorium Intybus Linaria vulgaris 



Crepis virens 



A relationship was found between the weed flora and the crop 

 dependent on the purity of the crop seed, the habit of growth of the 

 crop, and the character of the cultivation given. 



II. "A Study of the Methods of Estimation of Carbohydrates, 



especially in Plant Extracts." W. A. Davis & A. J. 

 DAISH. [ournal of Agricultural Science, 1913. 45, 

 437—468. 



A careful study has been made of the various methods by which 

 the sugars can be determined in crops and those most suitable have 

 been embodied in a scheme which has been found to work satisfac- 

 torily. 



