CHAP. V. 



DISENGAGEMENT OF CALORIC. 



279 



And it is here to be noticed, that those whose sexual ap- 

 paratus destroyed the most oxygen have the greatest quantity 

 of disk, and vice versa ; with the exception of Cobaea scandens, 

 in which the disk is very firm and persistent, and probably, 

 therefore, acts very slowly. 



When the cup-shaped disk of the male flowers of the 

 gourd was separated from the anthers, the latter only con- 

 sumed 1 1 '7 limes their volume of oxygen in the same space of 

 time which was sufficient for the destruction of sixteen times 

 their volume when the disk remained. The spathe of Arum 

 maculatum consumed, in twenty-four hours, five times its 

 volume of oxygen ; the termination of the spadix thirty times ; 

 the sexual apparatus 13'2 times, in the same space of time. 



An entire Arum dracunculus. in twenty-four hours, de- 

 stroyed thirteen times its volume of oxygen ; without its spathe 

 fifty-seven times; cut into four pieces, its spathe destroyed 

 half its volume of oxygen ; the terminal appendix twenty-six 

 times; the male organs 135 times ; the female organs ten times. 



The same ingenious observer also ascertained that double 

 flowers, that is to say those whose petals replace sexual 

 organs, vitiate the air much less than single flowers, in which 

 the sexual organs are perfect. 



Is it not then, concludes Dunal, probable that the conse- 

 quence of all these phenomena is the elaboration of a matter 

 destined to the nutriment of the sexual organs? since the 

 production of heat and the destruction of oxygen are in direct 

 relation to the abundance of glandular surface, and since these 

 phenomena arrive at their maximum of intensity at the exact 

 period when the anthei's are most developed, and the sexual 

 organs in the greatest state of activity. 



T 4 



