OUTLINES OF BOTANY. 
XXV 
129. The Calyx or flower-cup is commonly green and leaf-like, but not 
always so : the leaves of which it consists are named the Sepals. 
130. The Corolla, or inner row of floral envelopes, is commonly of 
delicate texture, and colored (that is, of some hue other than green), so that 
it forms the most showy part of the blossom : its several parts or leaves are 
called the Petals. 
131. When the leaves of the flower consist of one row only, that row is 
considered as the calyx, whatever its color or texture ; excepting where 
the real calyx has become obliterated, or concealed by adhesion with some 
other organ, as in most Umbelliferae (p. 153), when the envelope which ap¬ 
pears may be shown to belong to the corolla. A flower which is incom¬ 
plete from the want of the corolla is apetalous. 
132. The floral envelopes are collectively termed the Perianth, which 
name, however, is seldom used except in cases where the calyx and corolla 
are not satisfactorily distinguishable, or where the existence of both sets is 
uncertain, as in the Lily (p. 494), and Lily-like plants. 
133. Nor is the calyx, any more than the corolla, an essential part of the 
flower: both are often wanting, as in the Willow (p.424), and the Lizard’s- 
tail (p. 401) ; when the flower is naked, or achlamydeous. 
134. The leaves of the flower, whether sepals or petals, are more fre¬ 
quently than ordinary leaves (86) united, or grown together by their 
contiguous margins in various degrees, so as to form a cup or tube* which 
appears as if lobed, parted, cleft, or toothed (65), according to the degree of 
the union of the component parts. A calyx with the sepals thus combined 
is said to be monosepalous or monophyllous ; a corolla in the same way is 
monopetalous (or gamopetalous) ; and the degree of division, the number of 
parts, &c., are expressed by the same terms as in lobed leaves. 
135. To designate a calyx or corolla with unconnected (or distinct) se¬ 
pals or petals, the terms polyphyllous or poly sepalous, and polypetalons, are 
used ; or their number may be directly expressed, as ti'isepalous or tripeta- 
lous, when there are three, or 5-sepalous, 5~petalous , and so on. 
136. The mode in which the sepals or petals are applied to each other in 
the bud, constitutes the jestivation or prdefloration. The leading 
modes are, the valvule or valvular, where the parts meet by their edges 
without any overlapping, as in the calyx of the Mallow Family (p. 67) and 
the Linden (p. 71), the petals of the Vine (p. 85), &c.: the induplicate, which 
is a variety of the last, with the edges rolled inwards, as in the calyx of Clem¬ 
atis (p. 4) : the convolute, contorted, or twisted (forms that are all alike, ex¬ 
cept in degree), where each petal or sepal has one edge within and the other 
without, and consequently overlaps the next on one side while it is over¬ 
lapped by its neighbour on the other, as the petals of Mallow, St. John’s- 
wort (p. 51), and Flax (p. 72): the imbricated, where two of them have 
both edges exterior in the bud, so as to inclose the others; of which the 
quincuncial or spirally imbricated is the regular and principal form when the 
parts are five in number) as in the calyx-lobes of the Hose, the petals of 
the Cherry (p. 115), &.c. In this case, the first and second are wholly ex¬ 
ternal, the fourth and fifth wholly internal, while the third has one edge 
covered by the first, and the other overlapping the contiguous edge of the 
fifth ; and a line traced from the first to the adjacent edge of the second 
and so on to the fifth, describes a regular spiral. 
137. Frequently the petals, and rarely the sepals, are contracted below 
into a stalk-like base (the claw), when they are ungnicnlate, as in the corolla 
of the Mustard Family (p. 30); the expanded part, like the blade of the 
leaf, being distinguished as the lamina or limb. 
138. The calyx or corolla is regular when the parts are uniform in 
size and shape, as in the cruciform (cross-shaped) corolla of the Crucifer* 
c 
