316 



THE FRUIT. 



simple pistils united into one body, will normally dehisce in one 

 of two ways. Namely, either the carpels will separate at the line 

 of junction, thus resolving the pod into its constituent 

 elements ; or else, these parts remaining united, each 

 cell will open on the back by a splitting of the dorsal 

 suture. The former constitutes 



614. Septicidal Dehiscence (Fig. 582, 



584), so named because the capsule splits 

 through the septa or partitions (dissepi- 

 ments), each one separating into its two 

 constituent layers, one belonging to each 

 carpel. This occurs in Azalea and its 

 allies, in St. Johnswort, &c. The car- 

 pels, thus becoming separate, in these 

 cases open down their inner suture, 

 like a follicle, and discharge the seeds. 

 When the cells are only one-seeded, after separating septicidally, 



they often remain closed 



and fall away separately, 



as in Mallow, Vervain (Fig. 



985), &c. Such closed or 



nearly closed cells or car- 

 pels of a compound pistil 



are termed cocci. 



615. loculicidal Dehis- 

 cence is that in which the splitting opens into the loculaments (in 

 Latin, loculi) or cells ; that is, each carpel dehisces by its dorsal 

 suture (Fig. 583, 585), as in Iris, the Lily, Hibiscus, Evening Prim- 

 rose, &c. The dissepiments here are necessarily borne on the mid- 

 dle of the valves. 



616. In the Violet, &c. we have the loculicidal, and in several 

 khids of St. Johnswort the septicidal, plan of dehiscence in one- 

 celled capsules ; the placentas (answering to the partitions) being 

 borne in the former upon the middle of the valves ; while in the 

 latter each placenta is split in two, and one half borne on each mar- 

 gin of a valve. 



FIG. 5S2. Dehiscent capsule of Elodea, enlarged, showing septicidal dehiscence. 

 FIG. 583. Dehiscent capsule of Iris, showing loculicidal dehiscence ; the lower part cut 

 across, showing the dissepiments borne on the middle of the valves. 

 FIG. 584. Diagram (in cross-section) of septicidal, and, 585, of loculicidi^, dehiscence. 



