106 DROSERA ROTUNDJFOLIA. CHAP. 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 

 so, 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. 



