PHYSIOLOGY. WAG 
prisms. One drop of lymph of Euphorbia canari- 
ensis, Caput Medusae, Chara neriifolia had one or 
two prisms only. Alcohol congealed the lymph of 
the Euphorbia and precipitated a fibrous matter. 
Sulphuric acid had the same effect, but the fibres 
were not so thick as the former. The sap of Cheli- 
donium consisted of nothing but closely cohering 
globules. ‘This goes to prove, that the sap of some 
vegetables, for instance, the Potentilla anserina, is 
not, as Plenk supposes, merely decomposed or 
changed water. Rain found in those plants which 
consist of much cellular texture, ¢. ¢. the Musa 
paradisiaca, Strelitzia Regina, the globules smaller 
and less frequent than in the species of Euphorbia. 
§ 239. 
We shall soon find that plants with their whole 
surface, as far as it is green, with the stem and 
leaves, take up part of the atmospherical air and 
particles disposed in it, and again transmit air and 
moisture. And we cannot be much surprized to 
find, that the quantity of matter which they inhale 
from the atmosphere, and of that air and moisture 
which they exhale, is very great, if we consider that 
the number of apertures, which exist in the cuticle 
of plants, by lymphatics, (§ 236), in the green stalks, 
in both surfaces of the leaves, even in the flower and 
Its parts, is so very considerable. Hedwig counted 
in the Lilium bu/biferum in one surface of a single 
leaf 577 apertures in one cubic lme. A cubic foot 
would therefore according to this observation have 
about 998145 apertures. Now how many cubic 
O2 feet 
