20 
PLANT MORPHOLOGY. 
santalum rubrum, scilla, senega, sinapis alba, sinapis nigra, 
staphisagria, stamonii semen, taraxacum, triticum and vanilla. 
Leaves, herbs and flowers do not, as a rule, contain reserve 
starch. 
2. INULIN. 
Inulin was first observed by Valentin Rose in 1814 
in the root of Inula helenium. It appears to be an 
isomer of starch and occurs in solution in the cell sap 
of various members of the Compositse and various 
other families, being found in lower orders of plants 
only in isolated cases. 
It is stored chiefly in the parenchyma cells of the 
wood and bark of rhizomes, tubers and roots, being also 
found in the medullary ray cells. It occurs in a color- 
less, or yellowish, highly refractive, concentrated solu- 
tion, about 30 per cent, being present in plants during 
the early fall and spring, when it exists in greatest 
amount. During winter and also during summer it is 
changed to lsevulin. 
According to DragendorfT there are two forms of 
inulin ; one of which is amorphous and easily soluble 
in water, and another which is crystalline and diffi- 
cultly soluble in water. The latter is probably, how- 
ever, a modification of the former, and it is not unlikely 
that the various principles known as pseudoinulin, 
inulenin, helianthenin and synantherin are all modi- 
fications of inulin. 
If inulin-containing plants are preserved in alcohol 
and examined by aid of the microscope, the inulin will 
be found to have separated in the form of sphere- crys- 
talloids, which are attached to the cell wall ; but if the 
material is first allowed to dry out, the inulin will be 
found in irregular, almost gum-like lumps, which are 
with more or less difficulty dissolved, in water. 
In the latter form inulin is found in the following 
drugs : Inula, lappa, pyrethrum and taraxacum. 
