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Rh of heather seed as a form of food may be seen at a glance from the figures given in Tables III. and IV. It is often stated that in seasons when the corn has ripened well and early, the stock of Grouse in the following spring is healthy and vigorous, and the breeding season a good one; from this it has been argued that the same weather which has resulted in a good crop of grain has also produced a good crop of heather seed. This factor too may have something to do with the difference in the numbers of Grouse which moors in different parts of the country are capable of carrying. It is well known that the number of Grouse on a moor does not depend upon the area of heather land, for in the thinly-stocked moors of the west of Scotland the heather growth is stronger than in the south of Scotland, where in many districts there is a larger stock of birds. Even in Yorkshire, Lancashire, and Derbyshire the ground does not appear to be better suited for the growth of heather than in Scotland, yet in these counties the stock of district birds is proportionately much greater. The difference is partly to be accounted for by the fact already noted, that the heather in the north of England is of a better quality, that is to say with many more stalks to the acre, than the rank growth of the west of Scotland, but it has also been suggested that in the former country the normal weather conditions are more favourable to the ripening of the heather seed. Again, in Caithness, where the grain always ripens well on account of the long hours of daylight in the summer months, the stock of birds which the ground can carry is unusually large.

In September, October, and November, the tendency to revert gradually from summer to winter diet is well exemplified by the figures in Table III. Throughout these three months the consumption of the heather seed increases steadily, while "various" drops from 16 per cent, in September to 6 per cent, in November. In October we find the item of "brown winter heather" reappearing in the list, and in November we have a sudden increase in the consumption of blaeberry stalks and leaves, due probably to some temporary check suffered by the heather similar to that indicated by the figures for July. Turning now to Table IV. (p. 76) we find that in the four winter months the diet becomes more restricted. "Various" practically disappears, and its place is taken by a larger quantity of heather shoots, while heather seeds and blaeberry stalks still keep their place in the list. One or two points are worth noting. In the first place, the sudden drop in