186 



ESSENTIALS OF BOTANY 





Fig. 137. Chestnuts. 



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 akene (Fig. 136). 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 Grams, 



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. 



223. The Follicle. — One-celled, 

 simple pistils, like those of the 

 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. 138. Group of Follicles 

 and a Single Follicle of the 

 Monkshood. 



