When it persists as a massive element of the seed its nutritive function is usually apparent, for there is accumulated within its cells reserve-food, and according to the dominant substance it is starchy, oily, or rich in cellulose, mucilage or proteid.
In other cases the mucilage is denser and the branches more closely compacted (Helminthora).
The mucilage must be acidulated with hydrochloric acid before dialysing, to set free the gummic acid.
Assimilative layer, and may also by the production of mucilage be of use in the protection of the body in various ways.
Lemon juice is fermented for some time to free it from mucilage, then boiled 2 Cf.