262 DEHISCENT APOCAEPOUS FBTJITS. 



to a common axis or carpophore (KX^TTO;, fruit, and (pogea, I bear), 

 from which they are suspended at maturity. It is sometimes deno- 

 minated diachcenium (3< f , twice), from the union of two achaenia, which 

 in this instance receive the name of mericarps (fify oj , part), or hemicarps 

 (vfticrvs, half, and xx^vog, fruit). 



544. The Nut or Glans. This is a one-celled fruit with a hardened 

 pericarp, surrounded by bracts at the base, and, when mature, con- 

 taining only one seed. In the young state, the ovary contains two or 

 more ovules, but only one comes to maturity. It is illustrated by the 

 fruit of the Hazel and Chestnut, which are covered by leafy appendages, 

 in the form of a husk, and by the Acorn, in which the leaves or bracts 

 are united so as to form a cupola or cup (fig. 257). The parts of the 

 pericarp of the Nut are united so as to appear one. In Sagus, or the 

 Sago Palm, it is covered by peculiar closely applied scales, giving the 

 appearance of a cone. 



545. The Drupe (drupce, unripe olives). This is a succulent fruit 

 covered by a pericarp, consisting of epicarp, mesocarp, and endocarp; 

 and when mature, containing a single seed. This term is applied to 

 such fruits as the Cherry, Peach, Plum, Apricot, Mango, Walnut, 

 Nutmeg, and Date. The endocarp is usually hard, forming the stone 

 of the fruit, which encloses the kernel or seed. The mesocarp is 

 generally pulpy and succulent, so as to be truly a sarcocarp (Peach), 

 but it is sometimes of a tough texture, as in the Almond, and at other 

 times more or less fibrous. There is thus a transition from the Drupe 

 to the Nut. Moreover, in the Almond, there are often two ovules 

 formed, only one of which comes to perfection. In the Walnut, the 

 endocarp, which is easily separable into two, forms prolongations which 

 enter into the interior, and cause a remarkable division in the seed. 

 It has been sometimes called Tryma. In the Easpberry and Bramble, 

 several small drupes or drupels are aggregated so as to constitute an 

 Etcerio (tratlpos, a companion). 



546. Dehiscent Apocarpous Fruits. These open in various 

 ways, and usually contain more than one seed, being either 

 few-seeded, oligospermous (o'A/yo?, few, and wi^pa,, a seed), or 

 many-seeded, polyspermous (vo^t);, many). 



547. Follicle (folliculus, a little bag). This is a mature 

 carpel, containing several seeds, and opening by the ventral 

 suture (figs. 443, 468). It is rare to meet with a solitary 

 follicle forming the fruit. There are usually several aggre- 

 gated together, either in a circular manner on a shortened 

 receptacle, as in Hellebore, Aconite, Delphinium, and Ascle- 



piadaceae; or in a spiral manner on an elongated receptacle, as in 



Fig. 468. Follicle or dehiscent many-seeded carpel of Aquilegia vulgaris, Columbine. The 

 follicle dehisces by the ventral suture only. 



