108 DROSERA ROTUNDIFOLIA. Cuar. VL 
energetically. The angles or projections of the fibrous 
basis of the enamel and dentine (except, perhaps, in 
No. 4, which could not be well observed) were not in 
the least rounded; and Dr. Klein remarks that their 
microscopical structure was not altered. But this 
could not have been expected, as the decalcification 
was not complete in the three specimens which were 
carefully examined. 
Fibrous Basis of Bone.—I at first concluded, as 
already stated, that the secretion could not digest this 
substance. I therefore asked Dr. Burdon Sanderson 
to try bone, enamel, and dentine, in artificial gastric 
juice, and he found that they were after a considerable 
time completely dissolved. Dr. Klein examined some 
of the small lamelle, into which part of the skull of a 
cat became broken up after about a week’s immersion 
in the fluid, and he found that towards the edges the 
“matrix appeared rarified, thus producing the appear- 
ance as if the canaliculi of the bone-corpuscles had 
become larger. Otherwise the corpuscles and theiz 
canaliculi were very distinct.” So that with bone 
subjected to artificial gastric juice complete de- 
calcification precedes the dissolution of the fibrous 
basis. Dr. Burdon Sanderson suggested to me that 
the failure of Drosera to digest the fibrous basis of 
bone, enamel, and dentine, might be due to the acid 
being consumed in the decomposition of the earthy 
salts, so that there was none left for the work of 
digestion. Accordingly, my son thoroughly decal- 
cified the bone of a sheep with weak hydrochloric 
acid; and seven minute fragments of the fibrous 
basis were placed on so many leaves, four of the 
fragments being first damped with saliva to aid 
prompt inflection. All seven leaves became inflected, 
but only very moderately, in the course of a day. 
