NOTES AND QUERIES. 355 



curious appearance. I saw them several times repeat the performance. 

 I then placed a wire cage-trap under the tree, and in three days caught 

 nine of them. I have known them steal grapes and some other fruits, 

 but this is the first time in my life that I have known Rats steal and eat 

 gooseberries." 



Field Mice and Rooks. — While the attention of naturalists is being 

 drawn to the subject of Field Mice by the plague of these creatures which is 

 now devastating hundreds of acres of Scotch soil, it may not be uninteresting 

 to describe the systematic way in which, under favourable circumstances, 

 Rooks hunt and destroy them. In the winter of 1889, while living in the 

 Thuringia Wald, I noticed that a large stubble-field, a few hundred yards 

 from where I lived, was much frequented by Rooks. They seemed to be 

 standing about in an idle sort of way, excepting that they cawed rather 

 frequently, and thereby excited my curiosity. One or two of them had their 

 beaks buried up to the hilt in the ground, and remained for longer or shorter 

 times in such an attitude. They all flew away when I approached to 

 examine the spot. I could find no trace of any special operations, no digging 

 or scratching, and I was much puzzled as to what they were about. This 

 happened morning after morning, and the object of their assembling in the 

 stubble-field threatened to remain a perpetual puzzle to me in spite of all 

 my efforts to make it out. One frosty morning, however, it was all made 

 clear. The cawing of the original assemblages had evidently been successful, 

 and the field was almost covered with their coal-black confreres. They were 

 very silent and very busy, with their beaks buried in the earth and their 

 tails sloping upwards ; after remaining in this attitude for some seconds, 

 each one would, with a short, hurried movement forward, thrust his beak 

 in again. They were clearly hunting Field Mice. On visiting the field 

 next morning the whole plan of operations was clear There was not a 

 Rook to be seen ; but during the night a slight snow had fallen, which the 

 wind had scattered so that it lay only in the furrows and slighter depressions 

 in the soil. The beaks and feet of the Rooks of the day before had evidently 

 slightly crushed in the mice runs, and in the shallow furrows thus made the 

 snow was lying. An enormous irregular but close network of wavy white 

 lines was seen to spread out over the field. So close was this network of 

 runs that it was quite clear why so many Rooks were necessary. With a 

 small number it would be impossible to close the runs; hence a daily 

 assemblage with no result until by persistent cawing a sufficient number of 

 Rooks were gathered together for a successful systematic attack. The runs 

 are probably found by diligent probing of the ground with the beak, and 

 when found, are systematically worked in such a way that two or more Rooks 

 gradually approach one another. The unlucky Voles would thus find their 

 runs blocked up in all directions by the beaks of their enemies, slowly and 

 inexorably advancing towards one another. If undisturbed, it is clear that 



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