9 14 Brenchley . — The Development of the Gram of Barley . 
the dry weight of the straw. This shows that the dry weight of the grain 
in relation to the straw rises steadily for ten or eleven periods, then remains 
practically constant for about nine days longer, showing some inclination to 
fall for a few days before cutting, except in the plot C, which is later than 
the other two, and which may be somewhat slower in ripening. 
Fig. 1 6 shows the dry weight of the whole plant and the grain. The 
dry weight of the grain increases right up to the time that desiccation 
begins. As the curve remains flat from that time until harvest, it is 
0 .3 6 Q 12 15 13 21 24 27 JO J3 36 59 42 45 48 Days. 
Fig. i 6 . Dry weights of whole plant and grain. (Whole plant = weight of i,ooo grains + weight 
of straw calculated as being associated with i,ooo grains.) 
counterbalanced by immigration of material from the straw. In the whole 
plant, however, some fall in dry weight occurs after the beginning of desicca- 
tion, showing that from that time onward the intake of food material from 
the soil, if it still continues, is somewhat overshadowed by the destructive 
metabolic functions of the plant. In plot C the maximum dry weight of the 
whole plant is reached at an earlier date than in the other two plots, i. e. at 
the seventh or eighth period, which is such a critical point in the history of 
this plot. 
The nitrogen in the whole plant (Fig. 17) in the two normal plots would 
seem to reach its maximum at about the time at which desiccation sets in, 
remaining fairly constant afterwards. In C, on the other hand, the whole of 
