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HOW PLANTS GUUW FKOM TMK SKKD. 



Pea (Fi^. 42), and of all such j)liints, is (firofi/I/'t/ojioiui, that is, has a pair of 

 cotyledons, or seed-leaves, which is what the word nie^ms. Therefore all such 

 plants are called hicoTVLKDONous Plants. 



49. Pine-trees, and plants like them, f^onerally have more than 

 two cotyledons, in a circle; so their embryo is said to he poll/- 

 roti/lvtlniious ; meanin<i; " with sevr'ral or many cotylctlons." Fig. 

 49 is a magnified view ol a I'iiie-seed, di\ ided lengthwise, and 

 showing the long antl straight embryo lying in the middle of the 

 albumen. The slender lower part is the radicle or stendet ; the 

 uj)p('r part is a cluster of cotyledons or seed-leaves, in a close 

 bundle; three of them can be seen as it lies, and there are as 

 many more behind. Fig. 50 is this embryo as it comes up from 

 the seed, its cotyledons (six in number) ex[)anding at on.ce into 

 a circle of slender, needle-shaped leaves. 



50. It is ji pity these three words are so long; for th*^ pupil 

 should iix them thoroughly in his menu)ry ; because these differ- 

 ences in the embryo, or pluntlot in the .seed, run through the \\'hole 

 life of the plant, and show themselves in many other difTerencea 



which very strikingly distinguish oiu^ class of plants from another. J^et it be 

 remembered, therefore, tliat 



MonocotijledoiK )Hfi Phuitx, or MinioroitjJedoiis, are those which have only one 

 cotyledon or seed-leaf to their ei bryo. 



Dicotylfdououft I'lanfx, or DiiU'ti/hulon^i, are those which have a pair of coty- 

 ledons or .seed-leaves to their embryo. 



Polilcotilh'douoHft Plants, or /'o/i/cofi/Ir(h)iiK, are those which have more than 

 one pair of cotyledons or seed leaves to their embryo. 



Analysis of the Section. 



24. Flowei'8 produce Fruit ; this, the Sfoil ; of tliis tht> csstMiii.il part i.s the Embryo wliich grows. 

 35. It is alive ; but lies doriiiiuit a while How Icm^ soeils iii.iy 11 vo. 



26. Germiuation, tliebegiiiniiig of growth ; what is ueciiful for it. 27. What takes place, illustrated 

 from the Morniiig-Glory. 28. How the steinlet grows by Itiigtliciiinu, ami carries uptlie seed-leaves : 

 how the root is fornu'd and grows downwards. 29. lustimt of each jtart to turn in its proper direc- 

 tion ; and why. 30. Tile little seedling a coinpleto plant in miniature ; its ]>arts. 31. How it goes on 

 to grow : growth of tlie root ; rootlets; of the stem. Tiie Plumule or Bud. Developmeiktof thestem 

 piece by piece, each with its leaf. 



33. How the seedling is uourished at the beginning. Growth requires food. 33. How tliis is sup- 



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