DEMTSCENCE; CLASSIFICATION OF FRUITS. 



51 



ous other modifications and combiaationa 

 of the two forms may be discovered, but 

 do not call for a notice in this work. 



Dehiscence is secured by a peculiar 

 adaptation of the fibres to the other tis- 

 sues and to the form of the fruit. Vari- 

 ous forma of imperfect or incomplete 

 dehiscence are those in which it com- 

 mences at the apex and fails to extend 

 itself to the base, as in Cerastium (Fig. 

 274) and Eucalyptus (Fig. 275), or 

 in which it commences at the base and 

 extends only partially toward the apex, 

 as in Jussiaea (Fig. 276) and in Cinchona 

 (Fig. 277). Important pharmaceutical 

 decisions have rested upon the question 

 of basal or apical dehiscence. The true 

 Cinchona barks have all proceeded from 

 species whose fruits dehisce as repre- 

 sented in Fig. 277, while those of the 

 trees yielding the false barks dehisce as 

 represented in Fig- 278. 



The manner in which true dehiscence 

 passes into false or transverse dehiscence, 

 called Circumscissile, is well displayed by 

 Pigs. 279 to 281, all illustrations of closejy 

 related plants. A very curious form of 

 special dehiscence is that of Jeffersonia 



(Fig. 282). 



Dehiscence is not the only method by 

 which fruits open to discharge their seeds. 

 Rupturing fruits are those which open 

 by an irregular line. Some portion of a 

 pericarp may decay quickly, leaving an 



or the same result may be se- 



some part 



Our coa- 



in drying 



Openings 



openmer. 



of the very delicate tissue of 

 of this kind are called Fores, 

 cured by excessive shrinkage 

 of the pericarp, as in Fig. 283. 

 Bideration of this subject will close with 

 an illustration of the fruit of the Brazil- 

 nut (Lecyrhis, sp. Fig. 284). The apex 

 of this enormously thickened and strongly 

 hardened involucre consists of a small 



circular portion connected with the re- 

 mainder by a circle of tissue which 

 quickly decays and becomes movable, 

 thus leaving an apical pore. 



CLASSIFICATION OF FRUITS. 



A perfect or even fairly satisfactory 

 classification of fruits has never been pre- 

 sented, and it is impossible, except through 

 a complete revision and uniform agree- 

 ment of terminology, based upon a uni- 

 form set of principles. A classification of 

 some sort is, however, an essential in 

 pharmaceutical botany, and such a one is 

 here presented as appears most service- 

 able to those for whom it is intended. 



Among all the various systems which 

 have been proposed two fundamental 

 principles have been observed — first, the 

 morphological structure; second, the 

 physiological features. By the first, fmita 

 have been classed according to the char- 

 acter and number of the parts entering 

 into their formation and the modifications 

 which these have undergone in fructifica- 

 tion. By the second, according to the 

 structural characters as seen in the com- 

 plete fruit, without regard to their mode 

 of origin. As characters of the latter 

 kind exist for the sake of the offices which 

 they are to fulfil it is clear that physiology 

 forms the basis of the latter method of 

 classification. Although it is impractica- 

 ble to follow either system without some 

 regard to the other, it may be said that 

 to follow in the main the morphologic*il 

 plan is the more scientific, the other th© 

 more convenient and the more practical, 

 especially in economic work. This is 

 therefore the plan which is here adopted. 



Fruits possessing pericarps fitted for 

 transportation will then form the first of 

 our two classes, while those fitted for 

 discharging their seeds iP situ upon ma- 

 turity will form the second. 



For a few fruits not readily introduced 

 to this key, and for some exceptions, see 

 the explanations which follow: 



Fruits with pericarp designed for 

 transportation (a). 



Fruits with pericarp not designed 



for transportation (e). 

 With fleshy pericarp (Carnose) (b). 



With non-fleshy pericarp (Siccose) 



(c). 

 With seeds imbedded in a soft endo- 



carp (g). 



With seeds enclosed in a putamen 



(h). 



( 



b 



