246 



MANUAL OF BOTANY 



Fig. 525, 



f, 





^U 



Fig. sae. 



carpels separate with a certain amount of elasticity from the 

 axis to which they are attached, as in some Euphorbiacese, they 

 have been called cocci {fig. 543, c, c, c). By some botanists, 

 all carpels ■which thus separate from the axis in a septioidal 

 manner are termed cocci, and the fruit is described as dicoccous, 

 tricoccous, &o., according to their number. It is better to call all 



fruits, the carpels of which 

 separate from each other 

 without opening — schizo- 

 carps; and to consider 'them 

 indehisoent. fruits, as the 

 primary splitting does not set 

 the seeds free. 



In certain fruits, such as 

 those of Linum catharticum, 

 the ovaries open first by their 

 dorsal suture, and then sepa- 

 rate from each other in a 

 septicidal manner. 



2. Transverse oe Oir- 

 cuMscissiLE Dehiscence. — 

 In this kind of dehiscence 

 the opening takes place by a 

 transverse fissure through the 

 pericarp across the sutures, 

 so that the upper part is se- 

 parated from the lower like 

 the lid of a j ar or box, as in Hyoscyamus {fig. 527) and Ana- 

 gallis {fig. 560). Sometimes the dehiscence only takes place 

 half round the fruit, as in Jeffersonia, in which case the lid re- 

 mains attached to the pericarp on one side, as by a hinge. 



In the Monkej'-pot {fig. 528), the lower part of the ovary is 

 adherent to the tube of the calyx, and the upper portion is free ; 

 and when dehiscence takes place, it does so in a transverse 

 manner at the part where the upper free portion joins the 

 lower adherent one, so that it would appear as if the adherence 

 of the calyx had some effect in this case in producing the trans- 

 verse dehiscence. Such fruits are sometimes called operculate, 

 a term which is also applied by other botanists to all forms of 

 transverse dehiscence in which the upper portion of the pericarp 

 separates from the lower in the form of a lid or operculum. . 



Transverse dehiscence may also occur in fruits which are 

 formed by a single ovary or carpel, as well as in the compound 



Fig. 525. Diagram of 

 septifragal debis- 

 cence, in which 

 the valves have se- 

 parated from the 

 placentas, which 

 remain as a central 

 column with the 

 seeds attached. 

 Fig. 526. Fruit of a 

 species of Oerrni- 

 mm. c. Persistent 

 calyx, a. Axis or 

 carpophore from 

 whicli the ovaries, 

 0, o, with their 

 styles, t, t, are se- 

 parating. 5. Stig- 

 mas. 



