156 REPRODUCTIVE ORGANS. CHAP. Ill, 



sometimes the margin, as in the Pea. In the Pink 

 the receptacle is the central column, and in com- 

 pound flowers the receptacle of the florets is also 

 the receptacle of the seeds, exhibiting the same 

 variety of form and surface. 



By the spontaneous separation of the valves of 

 the simple pericarp, and by the spontaneous sepa- 

 ration of the valves, or consequent opening of the 

 partitions of the compound pericarp, the contained 

 seeds are disengaged, or extricated. But all pe- 

 ricarps do not open by means of valves, even 

 though they should contain several distinct cells ; 

 for the seeds are often extricated merely by means 

 of one or more pores opening in the pericarp, and 

 forming a passage for their discharge. Sometimes 

 the pores are situated in the apex of the pericarp, 

 as in Antirrhinum Orontium ; sometimes in the 

 sides, as in Campanula; and sometimes in the 

 base, as in Lycopsis. 



If no opening is effected in either of the fore- 

 going modes, the fruit falls to the ground when 

 mature with the contained seed, which finally 

 bursts the pericarp in the process of germination, 

 and thus extricates itself. 



Naked Such are the general characteristics of the pe- 



ricarp, where a pericarp is present. But there are 

 some seeds, such as those of the labiate flowers, 

 which are altogether destitute of a pericarp, and 

 hence said to be naked. Gaertner, however, who 

 for depth and accuracy of research stands altogether 





