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PHARMACEUTICAL BOTANY 
name is applied to the fruit of the Hop, and also to the fruit of the 
Coniferce in which the naked seeds are borne on the upper surface 
of the woody scales. 
A Galbalus is a more or less globular multiple fruit formed of 
fleshy connate scales, as in Juniper. 
Histology of a Capsule, Vanilla. — The Vanilla fruit is a one-celled 
capsule formed by the union of three carpellary leaves and dehiscing 
by two unequal longitudinal valves. 
Microscopic Appearance of a Transverse Section. — Passing 
from periphery toward the center, the following structures present 
themselves: 
1. Epicarp, consisting of epidermis and hypodermis. The epidermis 
consists of a layer of thick-walled epidermal cells whose outer walls 
show the presence of a thin yellow cuticle. Stomata are present in 
this tissue. The epidermal cells contain protoplasm and brownish 
bodies. Some also contain small prisms of calcium oxalate and a 
few, vanillin crystals. The hypodermis is composed of one to several 
layers of collenchymatic cells with dark-colored contents. Its cells 
are somewhat larger than those of the epidermis and thicker-walled. 
2. Mesocarp, a broad region of somewhat loosely arranged large, 
thin-walled parenchyma cells becoming smaller in the inner zone of 
this region. Most of these cells contain brownish contents but some 
possess long raphides of calcium oxalate. If the section be mounted 
in phloroglucin solution (5 per cent.) and a drop of strong sulphuric 
acid is added, a carmine-red color will be observed showing the pres- 
ence of vanillin in this region. Several closed collateral bundles will 
be seen coursing through the mesocarp. 
3. Endocarp, an irregular line of inner epidermal cells which is 
differentiated into two regions, the interplacental region and the 
placental region. The interplacental (inner) epidermis shows its 
cells elongated into numerous thin-walled glandular hairs which con- 
tain an abundance of balsam; the placental region covers the six 
bifid placentae which extend into the cavity of the capsule. Its 
(inner) epidermis is composed of mucilaginous cells. 
4. Seeds. -These are minute blackish bodies attached to the pla- 
cental twigs of the placentae. Some of them may have been torn off 
in cutting the section. 
