14 THE OAK 
the egg-shaped body consists chiefly of two longitudinal 
halves, separated by a median plane which runs through 
the acorn from top to bottom. These two halves, lying 
face to face so closely that it requires the above manipu- 
lation to enable us to detect the plane of separation 
(fig. 2, 1), are not completely independent, however ; ata 
point near the narrower end each of them is attached 
to the side of a small peg-shaped body, with a conical 
pointed end turned towards the narrow end of the acorn. 
This tiny peg-shaped structure is so small that it may 
be overlooked unless some little care is exercised, but if 
the hard masses are completely torn apart it will be 
carried away with one of them. 
The two large plano-convex structures are called the 
cotyledons, or seed-leaves (fig. 2, c) and they, together 
with the small peg-shaped body, constitute the embryo of 
the oak. The peg-shaped body presents two ends which 
project slightly between the two cotyledons beyond the 
points of attachment to them; the larger of these ends 
has the shape of a conical bullet, and is directed so that 
its tip lies in the point of the narrower part of the acorn, 
the other, and much smaller end, is turned towards the 
broaderextremity of the acorn. The larger, bullet-shaped 
portion is termed the radicle (fig. 2, 7), and will become 
the primary root of the oak-plant ; the smaller, opposite 
end is the embryo bud, and is termed the plumule (fig. 2, 
pl), and it is destined to develop into the stem and leaves 
of the oak. If the observer takes the trouble to carefully 
separate the two large cotyledons, without tearing them 
