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ORGANS AND FUNCTIONS OF PLANTS. 



may be white, yellowish, or purple, it is always green 

 after germination. It may be simple and with- 

 out any division, as in corn, grass, lilies, and other 

 bulbs 1 ; or it may be formed of two lobes united base 

 to base, as in the bean and castor oil plant 2 ; upon 

 this principle Jussieu founded his system. But it is 

 inconsistent with this system, that the lobes may be 

 three, as in drooping cypress; five, as in larch; six, 

 as in deciduous cypress; and even ten or twelve, as in 

 the pine fir. Sometimes it is difficult to ascertain whe- 

 ther the lobes be one or more. In some cases, during 

 germination the seed-lobes remain below ground 3 , as in 

 the horse chestnut; in others they appear above ground 4 

 in the form of seed leaves 5 . 



Seed lobes in the bean, with the nutrient vessels branching 

 through them, a, a, root: b, b, gemlet. 



(1) In Latin, Plantce Monocotyledones. 



(2) In Latin, Plantee Dicotyledones. 



(3) In Latin, Cotyledones hypogei, 



(4) In Latin, Cotyledones epigei. 



(5) In Latin, Folia seminalia. 



