82 
PARTS OF THE PERICAEP. 
from injury, but it is furnislied with glands, which secrete such 
juices as are necessary for the growth and development of the 
ovules. 
The pistil in its simplest state consists of a carpel, or folded 
leaf, with ovules at its margin ; in the fruit the pericarp repre- 
sents the carpellary leaf, and the seed the ovules. The trans- 
formation of a leaf into a pistil is not more remarkable than the 
metamorphosis of a pistil into a fruit. As the ovary becomes 
mature it takes the name of jpericarp^ and in its growth becomes 
either woody or pulpy fruit. Pulpy fruits absorb oxygen gas, and 
throw oif carbonic acid : saccharine or sweet juices are elaborated 
in their cellular integument. In another stage, the pulpy sub- 
stance passes through a slight fermentation, the organization is 
disturbed, the juices sour, the pulp decomposes, and putrefaction 
ensues. Such is the change which takes place in pulj^y fruits 
during their progress toward maturity and subsequent decay. 
87. The ovary being fertilized, the parts of the flower which 
are not necessary for the growth of the fruit, usually fade, and 
either fall off or wither away. The pericarjp and seed continue 
to enlarge until they arrive at perfection. 
The pericarp often includes other parts of the flower besides the ovary, as the 
fruit of the hazel and oak consists of the ovary, bracts, and calyx united ; the 
apple and pear, of the ovary and calyx ; that of the pineapple, of the ovaries and 
floral envelopes of several flowers combined. Every kind of fruit we see, has been 
once the ovary or base of the pistil. The term fruit, in common language, is limited 
to pulpy fruits which are proper for food ; but in a botanical sense, the fruit iiiciude>-' 
the seeds and pericarps of all vegetables. The size of fruit is not usuallj^ propor- 
tioned to that of the vegetable which produced it. The pumpkin and gourd gi'ow 
upon slender herbaceous plants, while the large oak produces but an acorn. The 
variety in the colors of fruits is supposed to be owing to certain changes of the 
ahrornule, analogous to the phenomena in the change of colors in leaves before their 
decay. 
a. Id some fruits the pericarp consists of the epicarp^ the skm 
of the fruit, or membraneous part which surrounds it, and which 
is a kind of epidermis ; the sarcocarp^ or mesocarp^ a part more 
or less fleshy, corky, or coriaceous, often scarcely perceptible, 
and covered by the epicarp ; the endocarp^ an internal mem- 
brane of the fruit, which lines the cavity, and by its folds forms 
the partitions and cells. In the peach, for example, the skin is 
the epicarp J the pulpy cellular substance which absorbs the 
juices of the fruit, the sarcocarp i the shell which incloses the 
kernel, deprived of moisture, and rendered dry and tough, is the 
endocarp. The endocarp is also called the p^utamen. 
Fig. 98 represents a portion of the carpel or legume of the 
bean, cut transversely to show the structure of the pericarp ; 
epicarp^ or external epidermis, corresponding to the lower 
Use of the Ovary— Its name in a mature state— Pulpy pericarps.— 87. Perfecting of tiie pericarp and 
*eed — Organs sometimes included in pericarps, &c. — Color of fruits — a. Epicarp— Sarcocarp— Eudocatf 
