COEOLLA. 
65 
claw being analogous to the petiole, and the lamina to the ex- 
panded part of the leaf. The structure of petals is like that of 
leaves, except that the cellular tissue is more delicate, and the 
jibrous system, or veins, consists of spiral vessels without 
woody fiber; they have sometimes breathing pores, or stomata. 
The lamina (Fig. Y2, a) is the upper, and usually the thinner 
part of the petal ; its margin is sometimes entire^ as in the rose ; 
sometimes crenate, as in the pink. The daw (Fig. Y2, h) is 
the lower part of the petal, and inserted upon the receptacle ; 
it is sometimes very short, as in the rose ; in the petal of the 
pink (Fig. 72) it is long and slender. The limb and tube of 
nionopetalous corollas correspond to the claw and lamina of the 
Fig. 72. Fig. 73. Fig. 74. Fig. 75. Fig. 76. 
polypetalous. The corolla is superior when inserted above tlie 
germ, inferior when below. It is regular^ when each division 
corresponds to the other, as in the rose and pink. When the 
parts do not correspond with each other, a corolla is irregula/r^ 
as in the pea and the labiate flowers. 
72. Gamopetalous corollas may, according to their forms, be 
divided as follows : Bell-form {campanulate) ; here the tube is not 
distinct, but the corolla gradually spreads from the base. Fig. 
73 is the representation of a bell-form corolla ; it is monopeta- 
lous ; the limb {a) is five-parted ; calyx (5), five-parted ; corolla 
superior : the blue-bell of the gardens ofters a fine illustration 
of this kind of corolla. Funnelform^ having a tubular base, 
and a border opening in the form of a funnel, as the morning- 
glory (Fig. 74). Gup-sJiaped^ differing from funnel-shaped, in 
having its tube and border less spreading ; and from bell-form, 
in not having its tube appear as if scooped out at the base 
(Fig. 75). Salver form.^ from an ancient drinking-glass called 
a salver ; this has a flat, spreading border, proceeding from 
the top of a tube (Fig. 7 6). Wheel-form^ having a short border 
without any tube or with a very short one (Fig. 77) ; this kind 
of corolla may be seen in the mullein. Labiate^ or lipped (so 
called from a fancied resemblance to the lips of an animal), 
consists of two parts ; such corollas are said to be personate^ 
naving the throat closed ; or ringent^ with the throat open, as 
at Fig. 78 : this kind of corolla results from the unequal co 
72. Gamopetalous corollas. 
