186 ESSENTIALS OF BOTANY 
220. The Akene. — The one-celled and one-seeded pistils 
of the buttercup, strawberry, and many other flowers, 
ripen into a little fruit called an ekene (Fig. 186). Such 
fruits, from their small size, their dry consistency, and 
the fact that they never 
open, are usually taken for 
seeds by those who are not 
botanists. 
221. The Grain.— Grains, 
such as corn, wheat, oats, 
barley, rice, and so on, have 
the interior of the ovary com- 
pletely filled by the seed, 
and the seed-coats and the 
wall of the ovary are firmly united, as shown ‘in Fig. 6. 
222. The Nut.— A nut (Fig. 137) is larger than an 
akene, usually has a harder shell, and commonly contains 
a seed which springs from a single 
ovule of one cell of a compound 
ovary, which develops at the ex- 
pense of all the other ovules. The 
chestnut-bur is a kind of involucre, 
and so is the acorn-cup. The name 
nut is often incorrectly applied in 
popular language; for example, 
the so-called Brazil-nut is really a 
large seed with a very hard testa. Fic. 188. Group of Follicles 
223. The Follicle. — One-celled, 2244 Single Follicle of the 
simple pistils, like those of the i 
columbine or the monkshood, often produce a fruit which 
dehisces along a single suture, usually the ventral one. 
Such a fruit is called a follicle (Fig. 138). 
Fig. 137. Chestnuts. 
