274 =The Vitality of Toads enclosed in Stone and. Wood. 
We can therefore scarcely argue with certainty from the death of all 
these individuals within two years, as to the duration of life, which 
might have been maintained had they retired spontaneously and fallen 
into the torpor of their natural hybernization in good bodily condition, 
The results of our experiments amount to this; all the toads both 
large and small inclosed in sandstone, and the small toads in the lime- 
stone also, were dead at the end of thirteen months. Before the ex- 
piration of the second year, all the large ones also were dead; these 
were examined several times during the second year through the 
glass covers of the cells, but without removing them to admit airs 
they appeared always awake with their eyes open, and never ina 
state of torpor, their meagreness increasing at each interval in which 
they were examined, until at length they were found dead; those two, 
also, which had gained an accession of weight at the end of the first 
year, and were then carefully closed up again, were emaciated and 
dead before the expiration of the second year. si 
At the same time that these toads were enclosed in stone, four other 
toads of middling size were enclosed in three holes cut for this pur- 
pose, on the north side of the trunk of an apple tree ;_ two being pla- 
ced in the largest cell, and each of the*others in a single cell; the 
cells were nearly circular, about five inches deep and three inches in 
diameter ; they were carefully closed up with a plug of wood, so as 
to exclude access of insects, and apparently were air-tight; when 
examined at the end of a year, every one of the toads was dead 
and their bodies were decayed. on Ta 
- From the fatal Tesult of the experiments made in the small célls 
cut in the apple tree, and the block of compact sandstone, it seems 
to follow that toads cannot live a year excluded totally from atmos- 
pheric air; and from the experiments in the larger cells within the 
block of oolite limestone, it seems probable that they cannot sur- 
vive two. years entirely excluded from food ; we may therefore con- 
clude, that there is a want of sufficiently minute and accurate obser- 
vation in those so frequently recorded cases, where toads are said to 
be found alive within blocks of stone and wood, in cavities that had no 
communication whatever with the external air. The fact of my two 
toads having increased in’ weight at the end of a year, notwithstand- 
ing the care that was taken to enclose them perfectly by a luting of 
clay, shews how very small. an aperture will admit minute. insects 
sufficient to maintain life. In the cell No. 5, where the glass was _ 
slightly cracked, the communication though small was obvious; but 
