LESSON 10.] TIII-lIl AKIJANT.KSIKNT IN TIIK lUD. 



109 



by niakiiij; ;i lioriznnt.-il slice of llic fl()\v(>r-l)iiil wlwii just ready to 

 open ; ami it may be ex|in'ssed in diajj;ranis, as in Fig. 22.'J, '224. 



2S0, The pieces of the ealyx or tiie corolla eillier overlap each 

 other in the bud, or they do not. AVhen tliey do not, the a'stivation 

 is commonly 



V(t/rafe, as it is called when the j)ieces meet each other by their 

 abrupt edges without any infolding or overlapping ; as the calyx of 

 ^the Linden or Basswood (Fig. 22.')) and the Mallow, and the corolla 

 of the Grape, Virginia Creeper, &c. Or it may be 



LuhijiUcatc, which is valvatc with the margins of each piece pro- 

 jecting inwards, or involute (like the leaf in Fig. 152), as in the 

 calyx of Virgin's-Bower and the corolla of the Potato, or else 



Reduplicate, like the last, but the margins projecting outwards 

 /^;:c:^c==<v • instead of inwanls ; these last being mere vari- 

 l//^^'^^^'\\ ations of the valvate form. 

 /? // oTfQtoXp\ 'A' ^^^' ^^''*^" ^^^^ pieces overlap in the bud, it 

 ^fy^^ jn )) is in one of two ways : either every piece has 

 one edge in and one edge out ; or some pieces 

 ^^__^^ are wholly outside and others wholly inside. 



223 In the first case the activation is 



Conrolufe or hcisfecl, as in the corolla of Geraniimi (most com- 

 monly. Fig. 224), Flax (Fig. 191), and of the Mallow Family. 

 Here one edge of every petal covers the next 

 before it, while its other edge is covered by 

 the next behind it. In the second case it is 



Imhricftted or imbricate, or breaking joints, 

 like shingles on a roof, as in the calyx of Ge- 

 ranium (Fig. 224) and of Flax (Fig. 191), 

 and the corolla of the Linden (Fig. 223). In 

 these cases the i)arts are five in number; and the regular way then 

 is (as in the calyx of the figures above cite<l) to have two pieces en- 

 tirely external (1 and 2), one (3) with one edge covered by the first, 

 while the other edge covers that of the adjacent one on the other 

 side, .nnd two (4 and o) wholly within, their margins at least being 

 covered by the rest. That is, they just represent a circle of five 

 leaves spirally arranged on the five-ranked or § plan (187, 188, 

 and Fig. 143 - 14.t), only with the stem shortened so as to bring 

 the parts close tog«-ther. The spiral arrangi-incnt of the parts of 



FIG. 223. Section arnws llip ll. 

 Fid. a2». Scclii.ii acrois llir 11.. 



10 



rr-biid iif l.iiiilrn. 



r-biid ol (j'lTuiiiuui : the i 



L>|>als iiiiiiiliuriMl ill tlicii' orili>r 



