298 GENERAL CHARACTERS AND COMPOSITION OF THE FRUIT. 
unilocular ; while a compound fruit may have one or more cells, 
according as the dissepiments are absent or present, and the 
number of cells is indicated by similar terms to those used when 
speaking of the compound ovary (page 276). 
The fruit, like the ovary, necessarily possesses a placenta, 
to which the seeds are attached; and the same terms are 
used in describing the different kinds of placentation, as with 
those of the ovary ; these kinds are usually more evident in 
the fruit. 
The fruit, again, is described as superior or inferior, in the 
same sense as these terms are used in speaking of the ovary. 
Thus a fruit is inferior, when it is formed from an inferior ovary, 
in which case the calyx necessarily enters into its composition, 
as in the Melon, Apple, Pear, and Quince (jig. 473); or it is 
superior, as in the Poppy (jig. 32) and Pea (jig. 668), when the 
ovary is superior, and the calyx non-adherent. 
The base of the fruit is that point by which it is united to 
the thalamus ; the apex is indicated by the attachment of the 
style, hence in those ovaries where the style is lateral or basilar, 
as in many Rosacee (jigs. 638 and 639), Labiatze (jig. 609), and 
Boraginaceve (jig. 610), the organic apex of the fruit will be also 
thus situated, so that the geometrical and organic apices will 
then be very different. 
CoMPOSITION OF THE Fru1t.—The fruit when perfectly formed 
consists of two parts; namely, the pericarp, and the seed or 
seeds contained within it. In the majority of cases the peri- 
carp withers, and the fruit does not ripen, when the seeds are 
abortive. But there are many exceptions to this; thus, many 
Oranges and Grapes produce no seeds, but the pericarp is never- 
theless fully developed ; and in the Bananas, Plantains, and 
Bread-fruit, the pericarps develop most extensively, and become 
best adapted for food, when the seeds are chiefly or entirely 
abortive. Generally speaking, however, the development of the 
seeds and pericarp proceeds together after the process of ferti- 
lisation has been etfected, and then only perfect fruit can be 
formed ; for although in common language we apply the term 
fruit in those instances where no seeds are produced, yet strictly 
speaking such are not fully formed fruits, but only enlarged and 
swollen pericarps. 
Having now alluded to the seeds as a component part of the 
perfect fruit, we must leave their particular examination till 
we have become acquainted with the structure of the ovules, and 
now proceed, therefore, to the description of the pericarp. 
Pericarp.—In the majority of fruits the pericarp consists 
simply of the walls of the ovary in a modified state ; but, when 
the calyx is adherent, it necessarily presents a more complicated 
structure. The pericarp exhibits three layers or regions (fig. 
695), an external, called the epicarp or exocarp, ep; a middle, 
the mesocarp, mt; and an inner, the endocarp, en. The middle 
