ORGANS OF EEFEODUCTIOK. 



311 



the divisions taking place at the points of union of the different 

 paii's of pinnaj. 



3. Porous Dehiscence. — This is an irregular kind of dehis- 

 cence, in which the fruits open by little pores or slits formed in 

 their substance by a process called rupturing. These openings may 

 be either situated at the apex, base, or side of the fruit, hence they 

 are described accordingly, as apicular, lateral, or basilar. Ex- 

 amples of this kind of dehiscence occur in the Poppy (fy. 428), 

 in which a number of pores are placed beneath the peltate disc 

 to which the stigmas ai"e attached; in the Antirrhinum (Jig. 

 611), where there are two or three orifices, one of Avhich is 

 situated near the summit of the upper carpel, the other ( one or 

 two) in the lower; and 



m various species of 

 Campanula, &c. (figs. 

 671 and 672). In the 

 latter the calyx is 

 adherent to the ovary, 

 and the pores wliich 

 have a very irregular 

 appearance at their 

 margins, penetrate 

 through the walls of 

 the pericarp formed 

 by the adherent calyx 

 and ovary; these pores 

 correspond to the num- 

 ber of cells in the 

 ovary, and are either 

 situated at the side 

 (fig. 671), or towards 

 the base (fig. 672). 

 IvixDS OF Fruit.- 



Fig. 671. 



Fig. 672. 



Fig. 6"1. Fruit of a species ot Campanula, p. 

 Pericarp, t, t Pores at the sides, c. c- Per- 

 sistent calyx united with the pericarp 



Fig- 672. "Fruit of a Campanula dehiscing 

 by pores at its base- 



A number of different kinds of fniit 

 have been distinguished and named, and several classifica- 

 tions of the same have been proposed at various times, but at 

 present there is but little accordance among botanists upon 

 this subject. This is much to be regretted, as there can be no 

 doubt but that a strictly definite phraseology of fniits, founded 

 essentially upon the structure and position of the ovary, would 

 be of great value in descriptive botany. The difficuhies attend- 

 ing this subject have been also much increased, by the same 

 names having been given by different authors to totally distinct 

 kinds of fruits, and even to different classes of fruits. In a 

 work like the present it would be impossible, and indeed would 

 only lead to confusion, if it were attempted to describe all the 

 different kinds of fruits that have received names. At the 

 same time, I consider the subject of far too much importance to 

 be hastily disposed of, and I shall accordingly devote as much 

 X 4 



