NATURAL THEOLOGY. 373 



Strongest frosts. On the approach of \v arm wea- 

 ther, this gum is softened, and ceases to be a hin- 

 derance to the expansion of the leaves and flowers. 

 All this care is part of that system of provisions 

 which has for its object and consummation the 

 production and perfecting of the seeds. 



The SEEDS themselves are packed up in a cap- 

 sule, a vessel composed of coats, which, compared 

 with the rest of the flower, are strong and tough. 

 From this vessel projects a tube, through which 

 tube the farina, or some subtile fecundating efflu- 

 vium that issues from it, is admitted to the seed. 

 And here also occurs a mechanical variety, ac- 

 commodated to the different circumstances under 

 which the same purpose is to be accomplished. In 

 flowers which are erect, the pistil is shorter than 

 the stamina ; and the pollen, shed from the antherae 

 into the cup of the flower, is caught in its descent by 

 the head of the pistil, called the stigma. But how 

 is this managed when the flowers hang down, (as 

 does the crown-imperial for instance,) and in 

 which position, the farina, in its fall, would be car- 

 ried from the stigma, and not towards it ? The 

 relative length of the parts is now inverted. The 

 pistil in these flowers is usually longer, instead of 

 shorter, than the stamina, that its protruding sum- 

 mit may receive the pollen as it drops to the ground. 

 In some cases, (as in the nigella,) where the shafts 

 of the pistils or stiles are disproportionably long 

 they bend down their extremities upon the antherae, 

 that the necessary approximation may be effected. 



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