THE FLOWERS AND FRUIT. 



VI. The Fruit. 



The Fruit is the germen or ovary arrived at maturity. It is 

 composed essentially of two parts, the Pericarp or Seed-vessel, 

 and the Seed. Many fruits, of small size, and having the peri- 

 carp closely enveloping the seed, were considered by Linnaeus 

 and others as naked seeds, but are now known to be true fruits, 

 and not merely seeds. In the description of plants, however, 

 as a matter of convenience, these small hard fruits are usually 

 called naked seeds. The only naked seeds known, however, 

 are confined to the Pines, Firs, and Cycases. 



The Pericarp, or part which immediately invests the seed or 

 seeds, and originally formed the germen or ovary, varies ex- 

 tremely in size, thickness, and texture. It is always formed 

 of three parts : the Epicarp, Mesocarp, and Endocarp. The 

 Epicarp, is an external thin membrane or skin ; the Mesocarp, 

 is the layer immediately under the epicarp, and may be thin or 

 thick, dry or juicy ; the Endocarp, is the innermost membrane, 

 varying in texture, and bounding the cavity which contains the 

 seed. Thus, in the Cherry, the glossy skin is the Epicarp; 

 the pulpy mass is the Mesocarp, and the hard shell covering 

 the seed is the Endocarp. 



Of the very numerous varieties of Fruits, the following may 

 be mentioned : 



1. The Capsule (Fig. 137.) is a dry seed-vessel, generally of 

 a membranous texture. It frequently splits in a regular man- 

 ner into several parts when ripe. These parts are called valves. 

 Internally it consists of a single cavity, in which case it is 

 called one-celled or unilocular ; or of two or more cavities. 

 These cavities or cells are separated by partitions or dissepi- 

 ments ; and there is often a central stalk or column, to which 

 the seeds are attached. 



2. The Pod or Siliqua (Fig. 138.) is a long dry seed-vessel, 

 of two pieces or valves, separated by a longitudinal partition, to 

 the edges of which the seeds are alternately attached. When 

 the Pod is as broad as long, it is called a Pouch or Silicula, as 

 in Fig. 139. 



3. The Legume (Fig. 140.) is a dry elongated seed-vessel, 

 formed of two oblong valves, without any longitudinal partition, 

 and bearing the seeds along one of its margins only. 



4. The Nut (Fig. 141.) is a seed covered with a hard peri- 

 carp or shell which does not burst. The seed is called the ker- 

 nel. 



