Boe 7 NS tructural By Ph ysiological Botany 
Order 1. COMPOSITA&. This order is not only one of the ee . 
but one of the best characterised and most natural in the vegetable 
kingdom. It numbers about twelve thousand species distributed over 
the whole surface of the globe. The species are herbaceous, rarely 
shrubby, and often (Ligulifloree) containing a 
milky latex ; the leaves are exstipulate and usually 
alternate. The flowers are hermaphrodite, male, 
female, or neuter (containing neither stamens nor 
pistil). They are placed on a common broadly © 
expanded receptacle, and are crowded into a ~ 
capitulum, and surrounded by a general involucre 
of densely crowded bracts. The individual flowers 
are usually situated in the axils of small bracts, 
which are called jalee, and the receptacle is then 
said to be paleaceous ; when they are absent it is 
maked. Rarely each flower has a special invo- 
lucel. YVhe calyx consists of an epigynous tube, 
the free margin of which developes after the 
withering of the flower, sometimes remaining 
membranous and entire, but usually transformed 
into bristles, hairs, scales, or a silky pappus (see 
p- 127). . The corolla is always gamopetalous, 
| and is usually 5- but sometimes 4- or 3- 
Fic. so02.— Pistil of cleft, is either ‘ular and regular, or bzabiate, 
ae (mag- having in the latter case two divisions in the upper 
and three in the lower lip, or “gulate. The five. 
stamens are attached to the corolla-tube and are » 
alternate with its teeth ; their filaments are free, 
but their anthers coherent into a tube (symgene- 
stous), always furnished at the apex with one, 
sometimes at the base with two appendages. The 
ovary is inferior and unilocular, and contain a 
| single straight pendulous ovule. - The style is 
ae oe divided in the upper part, and is usually furnished 
Intybus,’ with co- with collecting hairs which act like a brush in col- 
Ee ded). pepe" lecting the pollen. The fruit is an achene con- 
taining a single seed without endosperm. The  — 
flowers (florets) of the central part of the capitulum, are often of a — "a 
different structure and colour from those of the margin; and the two ~ 
kinds are hence often called florets of the disc and florets of the hee ie 
[The order is divided into three suborders, as follows :— ae, 
1. Ligulifore. - Flowers all hermaphrodite and he ; yes with ch 
. ag 
