UNORGANIZED CELL-CONTENTS. 
33 
The mucilages are further distinguished by their 
behavior toward reagents; those which are colored 
blue by chlor-zinc-iodide, and are soluble in ammoni- 
acal solution of cupric oxide, are known as cellulose 
mucilages. To this class belong the mucilages of the 
corm of salep and the seeds of cydonium. Most of the 
other mucilages, particularly the pectose-mucilages, 
are colored by alcoholic and glycerin solutions of the 
basic aniline dyes. 
Mucilage which occurs in colls containing raphides 
is stained by corallin, which is not usually the case 
with the other mucilages. 
2. OILS, RESINS AND ASSOCIATED PRODUCTS. 
Oils, resins and their associated products, like the mu- 
cilages and tannins, are formed in the plant either as a 
result of the activities of the protoplasm, or by reason of 
abnormal or pathological changes in some of the con- 
stituents of the cell. The oils may be divided into two 
principal classes, namely, the reserve or fixed oils, which 
are more or less intimately associated with the proto- 
plasm in fruits and seeds ; and the volatile oils which 
occur in sjfecial cells or special reservoirs . 1 The vola- 
1 Oil is found either in special secretion cells or in special reser- 
voirs. The former are large parenchyma cells, the walls of which 
are not infrequently suberized, and are found in rhizomes, as of cala- 
mus and ginger ; in harks, as sassafras and cascarilla ; in fruits, as 
capsicum, cubeba, piper and cardamomum. Oil secretion reservoirs 
are cavities formed either as a result of the enlargement of the 
intercellular spaces, caused by the separation of the cells, or by 
the disintegration of a number of cells. The former are spoken 
of as being schizogenous in origin, and the latter as lysigenous. 
These terms are also used to designate similar reservoirs holding 
mucilage, gum-resins and other products. The schizogenous reser- 
voirs are of more common occurrence, and are found in inula, 
arnica rhizome, caryophyllus and the umbelliferous fruits and 
various leaves, as eucalyptus and pilocarpus. 
