XXX11 FIRST PRINCIPLES 



429. The axis of the fruit is often called columella; the space where two car- 

 pella unite is named the commissure. 



430. All fruits which are mere modifications of a single carpellary leaf (354) have 

 always a suture corresponding with the junction of the margins, or with the placentae, 

 and often another corresponding with the midrib of the carpellary leaf: the former 

 is called the ventral, the latter the dorsal suture. 



431. If the pericarp neither splits nor opens when ripe, it is said to be indehis- 

 cent ; if it does not split or open, it is said to dehisce, or to be dehiscent ; and the 

 pieces into which it splits are called the valves. 



432. The dehiscence of the pericarp takes place in different ways. 



433. If it takes place longitudinally, or vertically, so that the line of dehiscence 

 corresponds with the junction of the carpella, the dissepiments are divided, the cells 

 remain closed at the back, and the dehiscence is called septicidal; Ex. Rho- 

 dodendron. 



434. Formerly, botanists said that in this kind of dehiscence the valves were 

 alternate with the dissepiment : or, that the valves had their margin turned 

 inwards. 



435. If it takes place vertically, so that the line of dehiscence corresponds with 

 the dorsal suture (430), the dissepiments remain united, the cells are opened at 

 their back, and the dehiscence is called loculicidal ; Ex. Lilac, Lily. 



430. Formerly it was said that in this kind of dehiscence, the dissepiments were 

 opposite the valves. 



437. When a separation in the pericarpium takes place across the cells horizon- 

 tally, the dehiscence is transverse ; Ex. Anagallis. 



438. If the dehiscence is effected by partial openings of the pericarpium, it is 

 said to take place by pores ; Ex. Poppy. 



439. Sometimes the cells remain closed, separating from the axis, formed by the 

 extension of the peduncle (387) ; Ex. Umbellifene, Euphorbia. 



440. Or the cells open and separate from the axis, which is formed by a cohesion 

 of the placentae which separate from the dissepiments ; Ex. Rhododendron. 



441. Sometimes the dissepiments cohere at the axis, and separate from the valves 

 (431) or back of the carpella; Ex. Convolvulus. 



442. All fruits are either simple or multiple. 



443. Simple fruits proceed from a single flower ; Ex. Pu3ony, Apple, Nut, Straw- 

 berry. 



444. Multiple fruits are formed out of several flowers ; Ex. Fir, Pine-apple, Fig. 

 They are masses of inflorescence in a state of adhesion. 



445. Simple fruits are either the maturation of a single carpellum (354), or of a 

 pistillum formed by the union of several carpella (363). 



446. Of fruit formed of a single carpellum, the most important are the Follicle 

 (447), Legume (448), Drupe (451), Akenium (452), Caryopsis (454), and Utricle 

 (455). r 



447. The Follicle is a carpellum dehiscing by the ventral suture, and having no 

 dorsal suture ; Ex. Pscony. 



448. The Legume is a carpellum having both a ventral and dorsal suture, and 

 dehiscing by both, either, or neither; Ex. Pea. 



449. The two sutures of a legume sometimes form what is called a replum; Ex. 

 Carmichselia. 



450. When articulations take place across the legumen, and it falls into several 

 pieces, it is said to be lomentaccous ; Ex. Ornithopus. 



451. The Drupe differs from the follicle in being indeliiscont, and in its pericar- 

 pium having a distinct separation of cpicarp (426), sarcocarp, and endocarp ; Ex. ;i 

 Peach. 



452. The Akenium is an indehiscent, bony, one-seeded pericarpium, which does 

 not contract any degree of adhesion with the integrnent of the seed ; Ex. Straw- 

 berry. 



453. It is a drupe, the pericarp of which docs not separate into three layers. 



454. The Caryopsis is an indehiscent, membranous, one-seeded pericarpiun), 

 which adheres firmly to the integument of the seed ; Ex. Corn. 



455. Utricle is a caryopsis, the pericarpium of which has no adhesion with the 

 integuments of the seed ; Ex. Eleusine, Chenopodiiun. 



