430 
POPULAR SCIENCE REVIEW. 
the leaves, and that the contents of these glands are altered, which has "been 
regarded as evidence of the digestion of the captured insects, is regarded by 
M. Hochstetter rather as a sign of injurious action, such as is produced by 
acids and gases noxious to the life of the plant. He refers to the injurious 
action of ammonia upon plants placed in a fresh hotbed with the frames 
closed ; and considers the saccharine excretion of leaves attacked by aphides 
to be a morbid phenomenon analogous to the increase of the fluid excretions in 
the plants in question. Thirdly, he remarks that Dioncece cultivated under 
bell-glasses are much stronger and more healthy than those grown in the 
open and allowed to catch flies. From all this M. Hochstetter concludes 
that the necessity or even the usefulness of the digestion of insects by plants 
is still far from being incontestably proved. 
Milk of the Cow-tree. — M. Boussingault, when at Maracay, in South 
America, made a rough examination of the milky fluids furnished by this 
celebrated tree ( Brosimum galactodendrori), which is widely distributed in 
tropical America. He obtained from it — 
1. A fatty substance like bee’s-wax, fusible at 50° 0., partially saponifiable, 
very soluble in ether, but slightly soluble in boiling alcohol. This sub- 
stance when melted and cooled resembled virgin wax, and candles were 
made of it. 
2. An azotized substance analogous to caseum. 
3. Saccharine matters. 
4. Salts of potash, lime, magnesia, phosphates. The quantity of solid 
matter in the milk was estimated at 42 per cent. 
Samples of this milky juice sent to the Paris Exhibition of the present 
year, gave a dried extract, 100 parts of which furnished — 
Wax, fatty matter 
. 84-10 
Sugar, inverted 
. 2-00 
Sugar, inversible 
. 1-40 
Gum, saccharifiable 
. 3-15 
Caseum, albumen ..... 
. 4-00 
Ash, phosphates 
. 1-10 
Undetermined non-nitrogenous substances . 
. 4-25 
100-00 
Which, brought to milky juice containing 42 per cent, of solid matter, 
gives — 
Wax and saponifiable matters . 
. 35-2 
Saccharine and analogous substances . 
. 2-8 
Caseum, albumen .... 
. 1-7 
Earths, alkalies, phosphates 
. 0-5 
Undetermined substances . 
. 1-8 
Water 
. 58-0 
1004) 
Thus in its general constitution, the milk of the cow-tree approaches cow’s 
milk, except that it contains about three times as much solid matter ; so that 
it is rather to cream that we must compare this vegetable milk. A cream 
analysed by M. Jeannier gave — 
