98 DROSERA ROTUNDIFOLIA. [Cuar. VI. 
ordinary temperature of a room. Here, then, at last, we 
have a case in which it appears that there exists an essential 
difference in digestive power between the secretion of Drosera 
and gastric juice; the difference being confined to the 
ferment, for, as we have just seen, pepsin in combination 
with acids of the acetic series acts perfectly on gluten. I 
believe that the explanation lies simply in the fact that 
gluten is too powerful a stimulant (like raw meat, or 
phosphate of lime, or even too large a piece of albumen), and 
that it injures or kills the glands before they have had time 
to pour forth a sufficient supply of the proper secretion, 
That some matter is absorbed from the gluten, we have clear 
evidence in the length of time during which the tentacles 
remain inflected, and in the greatly changed colour of the 
glands. 
At the suggestion of Dr. Sanderson, some gluten was left 
for 15 hrs. in weak hydrochloric acid (*02 per cent.) in order 
toremove thestarch. It became colourless, more transparent, 
and swollen. Smé4ll portions were washed and placed on five 
leaves, which were soon closely inflected, but to my surprise 
re-expanded completely in 48 hrs. A mere vestige of gluten 
was left on two of the leaves, and not a vestige on the other 
three. The viscid and acid secretion, which remained on the 
discs of the three latter leaves, was scraped off and examined 
by my son under a high power; but nothing could be seen 
except a little dirt, and a good many starch grains which 
had not been dissolved by the hydrochloric acid. Some of 
the glands were rather pale. We thus learn that gluten, 
treated with weak hydrochloric acid, is not so powerful or so 
enduring a stimulant as fresh gluten, and does not much 
injure the glands; and we further learn that it can be 
digested quickly and completely by the secretion. 
Globulin or Crystallin.—This substance was kindly prepared for 
me from the lens of the eye by Dr. Moore, and consisted of hard, 
colourless, transparent fragments. It is said* that globulin ought to 
“swell up in water and dissolve, for the most part forming a gummy 
liquid;” but this did not occur with the above fragments, though 
kept in water for four days. Particles, some moistened with water, 
others with weak hydrochloric acid, others soaked in water for one or 
two days, were placed on nineteen leaves. Most of these leaves, 
* Watts’ ‘ Dict. of Chemistry,’ vol. ii. p. 874. 
