RATS AND MICE. 
363 
statements was a very simple one. I recorded it in 
‘ Nature ’ as follows : — • 
It is, I believe, pretty generally supposed that rats and mice 
use their tails for feeding purposes when the food to be eaten 
is contained in vessels too narrow to admit the entire body of 
the animal. I am not aware, however, that the truth of this 
supposition has ever been actually tested by any trustworthy 
]> arson, and so think the following simple experiments are worth 
publishing. Having obtained a couple of tall-shaped preserve 
bottles with rather short and narrow necks, I filled them to 
within three inches of the top with red currant jelly which had 
only half stiffened. I covered the bottles with bladder in the 
ordinary way, and then stood them in a place infested by rats. 
Next morning the bladder covering each of the bottles had a 
small hole gnawed through it, and the level of the jelly was 
reduced in both bottles to the same extent. Now, as this 
extent corresponded to about the length of a rat’s tail if inserted 
at the hole in the bladder, and as this hole was not much more 
than just large enough to admit the root of this organ, I do not 
see that any further evidence is required to prove the manner 
in which the rats obtained the jelly, viz., by repeatedly intro- 
ducing their tails into the viscid matter, and as repeatedly 
licking them clean. However, to put the question beyond 
doubt, I refilled the bottles to the extent of half an inch above 
the jelly level left by the rats, and having placed a circle of 
moist paper upon each of the jelly surfaces, covered the bottles 
with bladder as before. I now left the bottles in a place where 
there were no rats or mice, until a good crop of mould had 
grown upon one of the moistened pieces of paper. The bottle 
containing this crop of mould I then transferred to the place 
where the rats were numerous. Next morning the bladder had 
again been eaten through at one edge, and upon the mould there 
were numerous and distinct tracings of the rats’ tails, resem- 
bling marks made with the top of a pen-holder. These tracings 
were evidently caused by the animals sweeping their tails about 
in a fruitless endeavour to find a hole in the circle of paper 
which covered the jelly. 
With regard to mice, the Eev. W. North, rector of 
Ashdown, in Essex, placed a pot of honey in a closet, in 
which a quantity of plaster rubbish had been left by 
builders. The mice piled up the plaster in the form of a 
heap against the sides of the pot 3 in order to constitute m 
