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78 to prove that birds sometimes find great difficulty in collecting a meal of wholesome food. The vast majority of winter crops contain, as we have already said, good dark green or dark reddish brown winter heather, sound wholesome food with a minimum of dead woody tissue. But now and again one finds a crop full of old woody growth of which the food value must be very small. And though the cause of this may sometimes be that the bird is a weakling and has been driven off the better feed to live upon whatever it can find elsewhere, yet this inferior food is sometimes found in the crop of a bird which is evidently no weakling. It may then be due to the fact that the moor has been left long unburned, and that all the heather within reach is old and rank. Or the moor may have been over-burnt from every point of view except that of the grazing tenant. In such a case large tracts of young heather are burned again and again, often by runaway fires, to bring the land to grass and kill the heather. In this the grazing tenants of parts of the borderland and of the north of England have been very successful, and heather in many places is a thing of the past, the moors being now almost all white land. Scattered through this, where the tussocky grass has had its way for many years, is a thin growth of useless straggling heather of little value as food for bird or beast. For the purpose of drawing up Tables III. and IV. two hundred and eighty-seven specimens of Grouse were examined, and the specimens were fairly evenly distributed over the months from April 1906 to March 1907. The specimens represented birds from no fewer than twenty-seven different counties, so that the results may be regarded as conclusive, so far as concerns the particular period under review.

In case, however, of the period selected being abnormal, Table V. (p. 79) was prepared to show the crop contents for two complete years, viz., 1906 and 1907. In this Table the figures for the corresponding months are placed together, and an average is struck for each month. It will be seen that these averages show the same general tendencies as are seen in the former Tables, and confirm the view that the figures given in Table III. for July and November 1906 were abnormal, and probably due to exceptional circumstances.

The total number of specimens examined for the purpose of drawing up Table V. was four hundred and thirty-six, including the two hundred and eighty-seven already included in Tables III. and IV.; but in 1907 specimens were