Cuar. XVI.] SECRETION, ABSORPTION, DIGESTION. 309 
and transparent. After 24 hrs. two of the cubes were completely 
dissolved, and already the secretion on these glands was almost wholly 
absorbed. After 42 hrs, the two other cubes were completely dissolved. 
These four glands began to secrete again after eight or nine days. 
(6) Two large cubes of albumen (fully 5 of an inch, 1°27 mm.) 
were placed, one near the midrib and the other near the margin 
of a leaf; in 6 hrs. there was much secretion, which after 48 hrs. 
accumulated in a little pool round the cube near the margin. This 
cube was much more dissolved than that on the blade of the leaf; so 
that after three days it was greatly reduced in size, with all the angles 
rounded, but it was too large to be wholly dissolved. ‘The secretion 
was partially absorbed after four days. The cube on the blade was 
much less reduced, and the glands on which it rested began to dry 
after only two days. 
(7) Fibrin excites less secretion than does meat or albumen. 
Several trials were made, but I will give only three of them. Two 
minute shreds were placed on some glands, and in 3 hrs. 45 m. their 
secretion was plainly increased. The smaller shred of the two was 
completely liquefied in 6 hrs. 15 m., and the other in 24 hrs.; but even 
after 48 hrs. a few granules of fibrin could still be seen through a 
lens floating in both drops of secretion. After 56 hrs. 30 m. these 
granules were completely dissolved. A third shred was placed ina little 
pool of secretion, within the margin of a leaf where a seed had been 
lying, and this was completely dissolved in the course of 15 hrs. 80 m. 
(8) Five very small bits of gluten were placed on a leaf, and they 
excited so much secretion that one of the bits glided down into the 
marginal furrow. After a day all five bits seemed much reduced in 
size, but none were wholly dissolved. On the third day | pushed two 
of. them which had begun to dry, on to fresh glands. On the fourth 
day undissolved traces of three out of the five bits could still be 
detected, the other two having quite disappeared ; but I am doubtful 
whether they had really been completely dissolved. Two fresh bits 
were now placed, one near the middle and the other near the margin 
of another leaf; both excited an extraordinary amount of secretion; 
that near the margin had a little pool formed round it, and was much 
more reduced in size than that on the blade, but after four days was not 
completely dissolved. Gluten, therefore, excites the glands greatly, 
but is dissolved with much difficulty, exactly as in the case of 
Drosera. I regret that I did not try this substance after having been 
immersed in weak hydrochloric acid, as it would then probably have 
been quickly dissolved. 
(9) A small square thin piece of pure gelatine, moistened with 
water, was placed on a leaf, and excited very little secretion in 5 hrs. 
30 m., but later in the day a greater amount. After 24 hrs. the whole 
square was completely liquefied; and this would not have occurred 
had it been left in water. The liquid was acid. 
(10) Small particles of chemically prepared casein excited acid 
secretion, but were not quite dissolved after two days; and the glands 
