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seeds may be picked out. The lower digitate leaves of the plant are seldom found in the drug. The
thin, longitudinally furrowed stems bear simple or lobed, stipulate bracts. These subtend the
bracteoles, enclosing the pistillate flowers. The bracts are stipulate and the lamina may be simple
or three-lobed. The bracteole enclosing each flower is simple. The perigone enveloping the lower
part of the ovary and the two reddish-brown stigmas can be seen with a lens.
The flowering tops consists of: short stems, upper leaves, bracts, bracteoles and female flowers
with few fruits.
The leaves are generally broken, alternate, petiolate and simple, but the lower leaves are
palmately divided and possess serrate margin.

Microscopical characters:

The resin is secreted by numerous glandular hairs. The head is usually 8-16 celled and the pedicel
multiseriate. To differentiate these from similar trichomes (e.g. those of the Labiatae) specific
stains can be used. These include Fast Blue Salt B and a reagent (consisting of vanillin in ethanolic
sulphuric acid) which stains the cannabis glands a deep reddish purple.
It is possible to analyse individual trichomes by GLC by which means it has been shown that the
glands represent a dynamic system in the cannabinoid synthetic activity of the plant. In addition,
abundant conical, curved, unicellular hairs, are also found, many having cystoliths of calcium
carbonate in their enlarged bases. Cluster crystals of calcium oxalate are abundant, particularly
in the bracteoles.

Constituents:

More than 400 different compounds have been isolated from cannabis.
1- The most commonly described is the narcotic resin (about 15-20 %) which is brown,

amorphous and semi-solid.
The resin contains over 60 compounds called Cannabinoids.
The most commonly described cannabinoids are:

• Delta-9-tetrahydrocannabinol (∆ 9-THC).
• Cannabidiol (CBD).
• Cannabinol (CBN), Cannabidiolic acid, Cannabigerol (CBG), Cannabichromene, etc.

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