THE COMMON MOLE, MOLDWARP OR WANT 25 



only one instance found a nest in which the component materials 

 were mixed with fur taken from the Mole's own body.^ He 

 believes that the presence of the fur was accidental, and due to 

 natural moulting of the coat. Sometimes the fur of other 

 animals, or the feathers of birds, especially rooks and fowls, find 

 their wayMnto the nest, but it is difficult to decide whether 

 fur or feathers are used knowingly or merely by chance.* 



" Nearly every fortress has a bolt-run, by which the mole 

 can escape when surprised in the nest. This run leads down- 

 wards from the bottom of the nest, and then turns upward and 

 out of the fortress by a tunnel of its own, and is very rarely 

 connected with any of the other numerous exits of the fortress. 

 The only fortresses that I have seen without the bolt-run have 

 been on marshy land, where such a tunnel would have led to 

 water."* (See Figs. 9 and 15.) 



" Occasionally one comes upon a downshaft, leading directly 

 from the nest downwards almost perpendicularly for sometimes 

 nearly three feet. The use of these downshafts is puzzling. 

 Where the land is low-lying and the soil moist they may be 

 intended to drain the nest, but this is inconceivable in the 

 Bunter sandstone on high ground above the level of the highest 

 floods, where I have found them on more than one occasion. 

 It has been stated that they are deliberately sunk as wells to 

 supply the mole with water, a notion which, I imagine, has arisen 

 from a flooded fortress having been explored. Figs. 4, 16, and 

 17 illustrate such fortresses, which came under my notice, but it 

 is ridiculous to suppose that the mole foresees the possible rise 

 of water from below, and equally ridiculous to suppose that he 

 digs the well through the water when it has risen." 



Mr Adams makes the suggestion that these downshafts are 

 abortive bolt-runs, which have been abandoned when it was 

 found that the right point to turn upwards had been missed, 

 a suggestion which he thinks gains probability from the fact 

 that when the downshafts occur the bolt-run is absent. 



' This nest was forwarded for my inspection, but, unfortunately, never reached me. 



^ As reported by W. Hi St Quintin, Field, 31st March 1883, 431, a nest contained, 

 besides moss and dried grass, two handfuls of fur and the mutilated body of a 

 recently killed mouse {Microtus agresHs), 



^ For a description of the actions of a mole when collecting leaves for its nest, 

 see note on p. 43 infra, * Adams. 



VOL. II. C 



