BOTANY. 93 
The peduncle is variously formed, experiencing greater modifications than 
the petiole. Sometimes the axis is shortened, so as to exhibit a flattened 
form, with flowers scattered over the surface. Here it becomes a receptacle, 
phoranthium, or climanthium. Sometimes the peduncle is abortive, and 
becomes converted into a tendril; at others, it is expanded and hollowed 
out at the apex. ‘The extremity of the peduncle is the thalamas, or 
torus. 
Inflorescence is of two kinds; one where the lower flowers on the stem 
are produced first, the other where they are last to appear. In the first 
kind of inflorescence, called indefinite, or axillary, the axis continues to grow 
and to develope new leaf buds, the upper being always less advanced than 
the lower ; or, if the axis be shortened, so that the peduncles stand crowded 
together, the central flowers are less advanced than the external. The 
expansion of the flower is thus centripetal. 
The simplest form of indefinite inflorescence is, where single flowers are 
produced in the axils of the ordinary leaves. The different subdivisions and 
their relative lengths give rise to a great variety of terms. When the 
primary peduncle is elongated, and gives off nearly equal pedicels, each 
bearing a flower, we have a raceme, as in the currant, and a panicle when 
the pedicels of the raceme are themselves branched. If the central 
peduncles of a dense panicle are longest, a thyrse is produced. A corymb 
is where the lower pedicels on a peduncle are elongated, so that all the 
flowers on the different pedicels are nearly in one plane; the corymb may 
be sample or compound, the secondary axis again subdividing in the latter 
case. When the pedicels are very short or absent, so as to render the 
flowers sessile, a spike is produced: this, when producing unsexual flowers, 
as in the willow, becomes an amentum, or catkin. It may also be succulent 
or pulpy, with the flowers invested by a sheathing bract or spathe, as in 
Arum; it is then called a spadiz. A spike bearing female flowers only, and 
covered with scales, is either a sfrobilws, as in the hop, or a cone, as in the 
pine. . 
When the primary axis is depressed, instead of being elongated, other 
forms are exhibited. Should the pedicels all spring from nearly the same 
point on the axis, we have an wmbel; when numerous flowers are placed 
on a nearly flat receptacle, and either sessile or nearly so, a capitulum, 
anthodium, or calathium is formed, as in the dandelion ; when the surface is 
more convex this is called a glomerule. A receptacle may be concave, and 
inclose the flowers, as it were; such an arrangement is called a hypante- 
odium, and is seen in the fig. 
In definite inflorescence, where the flower buds are all terminal, the 
main axis is first terminated by a blossom which terminates its growth. 
This gives a solitary terminal flower, as in the Tulip. Further development 
ean take place only by the production of axillary branches, which can 
spring from the primary peduncle only when it is furnished with bracts, from 
whose axils they may arise. The order of flowering is therefore from the 
apex downwards, or descending (the reverse of the indefinite forms) ; 
centrifugal, or from the centre outwards, if the blossoms are. on a level 
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