652 MURID^— MUS 



destroying far more than they eat by tainting it with their 

 droppings and unsavoury odour. By climbing curtains and 

 blinds they reach suspended bird-cages, stealing the seeds, and 

 not infrequently injuring or killing the birds. In stores, 

 warehouses, barns, granaries, and cornstacks they are, of 

 course, an unmitigated nuisance, and the cause of great 

 pecuniary loss. Immune from attack and multiplying in hosts, 

 they drill the whole interior of a cornstack, forming a labyrinth 

 of runs, and occasionally — with the assistance of Harvest and 

 Field Mice — make incalculable havoc amongst the grain. At 

 threshing, notwithstanding the fact that vast numbers succeed 

 in escaping, hundreds may be killed in a single rick.^ 



Like rats, the House Mouse shows a propensity for 

 following a definite track to and from its hole ; advantage 

 may be taken of this habit in trapping mice. It is often 

 said to be suspicious of traps, especially those smelling ot 

 previous occupants ; Adams [MS. ) says this is difficult to 

 prove or disprove, but he is inclined to disbelieve it, and 

 thinks that when House Mice refuse to enter traps, it is either 

 because they do not perceive the bait, or else because there 

 is other food more to their taste near at hand. They will 

 sometimes jump over traps placed in their path. Once when 

 much troubled with mice, we set a trap between a fender and 

 chimneypiece, through which aperture we had seen a mouse 

 running on several occasions from the fireplace. We sat 

 quietly watching the trap ; in due course the mouse came out 

 and leapt safely over the trap ; we gently tapped the floor 

 with a foot, and the mouse turned and jumped back again. 

 A few minutes later the mouse and we repeated this perform- 



1 This species frequently plays a great part in the development of a mouse plague. 

 Perhaps the most serious instance has been afforded recently by the great mouse 

 plague in South Australia and Victoria, in which the House Mouse was the chief 

 species involved. The plague developed in the bush as well as in the wheatland in 

 igi6 and 1917, after two abnormally heavy harvests. The wheat had been sold to 

 the British Government, and it lay stacked in bags ready for shipment. Ships were 

 lacking ; and the stacks remained unprotected from a possible attack by the rodents. 

 As cold weather approached, the mice invaded the stacks and quickly produced ruin 

 and disease. The damage done to wheat is estimated to be well over ^1,000,000, 

 and much damage was done also to other property. Myriads of mice were present ; 

 thus 70,000, weighing about one ton, were killed in an afternoon in one wheatyard 

 alone (Hinton, Rats and Mice as Enemies of Mankind, Economic Series, No. 8, 

 British Museum, igi8, p. 41). 



