FORM AND STRUCTURE 
Head, is like a spike except that the central axis is so short 
that the fowers form a compact cluster. 
Strobile, isa compact cluster with large scales concealing the 
flowers. 
FRUIT. 
The Fruit consists essentially of the ripened pistil. After 
the ovaries have been fertilized the ovary is called a Peri- 
carp. ‘The following kinds of fruits are those most frequently 
borne by trees and are the products of a single flower: 
Akene, is a one-seeded, dry, hard, seed-like fruit. 
Samara, resembles an akene except that it has a wing-like 
appendage. The Ash, the Elm and the Maple produce 
samaras. 
Glans or Nut, is a fruit with a thick hard pericarp, enclosed 
more or less in an involucre. The acorn is a nut, 
Drupe, is often called a stone fruit. In it the wall of the 
pericarp is differentiated into three divisions—the outer 
or skin called exocarp, middle or fleshy portion called 
mesocarp, the inner wall enveloping the seed called endo- 
carp. A cherry is a drupe. 
Tryma, is a fruit structurally resembling the drupe, but the 
mesocarp is harder, more fibrous, and the outer husk ulti- 
mately splits open and comes off. <A hickory nut is an 
example. 
Berry, has a thin rind and all the rest of the pericarp is suc- 
culent. Berries may be one or many-celled. Grape and 
currant are examples. 
Pome, is a fleshy fruit, the chief bulk of which consists of an 
adherent fleshy calyx. The apple isa pome. 
Legume, is a dry one-carpelled fruit or pod that splits open 
front and back. ‘The fruit of the Locust is a legume. 
Capsule, consists of two or more united pistils which open 
and allow the seeds to escape. 
Fruits that are the product of one flower but of more than 
one pistil are called Aggregated Fruits. Raspberry is an 
example. Fruits that are the products of flower clusters 
instead of single flowers are called Multiple Fruits. 
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