106 DROSERA ROTUNDIFOLIA. Cuar. VI. 
as Dr. Klein thinks, may be the result either of the 
incipient digestion of the fibrous basis or of all the 
animal matter having been removed, the corpuscles 
being thus rendered invisible. A hard, brittle, yellow- 
ish substance occupied the position of the medulla 
in the fragments of the hyoidal bone. 
As the angles and little projections of the fibrous 
basis were not in the least rounded or corroded, two of 
the bits were placed on fresh leaves. These by the 
next morning were closely inflected, and remained 
- 80,—the one for six and the other for seven days,— 
therefore for not so long a time as on the first occasion, 
but for a much longer time than ever occurs with 
leaves inflected over inorganic or even over many 
organic bodies. The secretion during the whole time 
coloured litmus paper of a bright red; but this may 
have been due to the presence of the acid super- 
phosphate of lime. When the leaves re-expanded, the 
angles and projections of the fibrous basis were as 
sharp as ever. I therefore concluded, falsely as we 
shall presently see, that the secretion cannot touch 
the fibrous basis of bone. The more probable expla- 
nation is that the acid was all consumed in decom. 
posing the phosphate of lime which still remained ; 
so that none was left in a free state to act in con- 
junction with the ferment on the fibrous basis. 
Enamel and Dentine—As the secretion decalcified 
ordinary bone, I determined to try whether it would 
act on enamel and dentine, but did not expect that it 
would succeed with so hard a substance as enamel. 
Dr. Klein gave me some thin transverse slices of 
the canine tooth of a dog; small angular fragments 
of which were placed on four leaves; and these were 
examined each succeeding day at the same hour. The 
results are, I think, worth giving in detail. 
