542 



PHANEROGAMS. 



The growth of ihe primary root of Monocotyledons soon ceases even when 

 it is very strongly developed during germination, as in Palms, Liliacese, Zea, &c. ; 

 lateral roots are produced in its place, springing from the axis, which are stronger 

 the higher up they are produced on it. No such permanent root-system is 



Fig. 383. — Germination of Pha-iiix ciacty^ifera : I transverse section 

 of the dormant seed; /// — //', difTerent stages of g-ermination (/Kthe 

 natural size) ; A transverse section of the seeil at .v-v in IV ; R transverse 

 section at xy, C at zz; f the horny endosperm, .? the slieath of the 

 cotyledon, st its stalk, r its apex developed into an organ of absorption 

 which gradually consumes the endosperm and at length occupies its 

 I lace, 7v the primary root, 7u' secondary roots, fi' b" the leaves which 

 succeed the cotyledon, b" becomes the first foliage-leaf: in />' and C its 

 folded lamina is seen cut across. 



Fig 3S9. — VX-aM. o{ Po!ygotiaf!i7n mnlliJJoruyn 

 in its second year ; B its stem magnified, lu the 

 unbranched primary root, iv' lateral roots spring- 

 ing from the stem st, I foliage-leaf of the second 

 year, k bud, c the scar where the cotyledon was 

 attached, i and 2 scars of the first sheath-leaves 

 which precede the foliage-leaf, /. /, // the 

 succeeding sheath or cataphyllary leaves of the 

 bud in B. (Cf. Fig. 135. p. 165.) 



developed from the primary root of jNTonocotyledons as is found in Gymnosperms 

 and in many Dicotyledons ; sometimes no roots at all are produced, as in some 

 Orchidaceous saprophytes destitute of chlorophyll (as Epipogium and Corallorhiza), 

 which never possess any roots. 



The plumule of the embryo is usually completely enclosed in a single 



