268 EARLY SPRING IN MASSACHUSETTS. 
course thoroughly wet, and, humanly speak¬ 
ing, uncomfortable, though the creature could 
breathe in it. But it is plain that the musk¬ 
rat cannot be subject to the toothache. I have 
no doubt this was made and used last winter, 
for the grass was as fresh as that in the meadow 
(except that it was pulled up), and the sand 
which had been taken out lay partly in a flat¬ 
tened heap in the meadow, and no grass had 
sprung up through it. In the course of the 
above examination I made a very interesting 
discovery. When I turned up the thin sod from 
over the damp cavity of the nest, I was sur¬ 
prised to see at this hour of a pleasant day what 
I took to be beautiful frost crystals of a rare 
form, frost bodkins I was in haste to name 
them, for around the fine white roots of the 
grass, apparently herds grass, which were from 
one to two or more inches long, reaching down¬ 
ward into the dark, damp cavern (though the 
grass blades had scarcely made so much growth 
above ; indeed the growth was scarcely visible 
there), appeared to be lingering still into the 
middle of this warm afternoon, rare and beau¬ 
tiful frost crystals exactly in the form of a 
bodkin, about one sixth of an inch wide at base, 
and tapering evenly to the lower end. Some¬ 
times the upper part of the core was naked for 
half an inch, which gave them a slight resem- 
