INTKODIJCTION.
acles or ampl.antha. They yaiy in colom-, fm™, size, and in the situation .viñch
tliey occupy on the plant. In some species of the section Uroüigma the receptacles
^vhiie youii- are enclosed in caiyptriform involucres, -«-hich arc thrown olí ut an early
s t a g e of the expansion of the receptacles. Tiiese hoodlike bodies pei-sist longer in
F. ulH,s>ma than in any other species, but on the whole they aro too fugacious to found
specific charactci-s upon. The hollow receptacle lias walls of more or less fleshy texture,
and its moutli is occupied by rows of bracts, which in the majority of cases so iiiterlock
as pmcticall y to close it. The lower of these bracts often bend do^™wal•ds into the cavity
of the receptacle, curving round the upper flowers; the middle bracts are more or less
liorizontal in direction ; while those towards the upper or outer part of the mouth project
therefrom, so as to be visible e^vternally and to form a more or less prominent apical
umbilicus. In a few species the mouth is surrounded externally by a more or less clearly
defined annulus, formed of coalesced bracts. In shape the receptacle varies from spheroidal
to ovoid, ellipsoid, obovoid, or pp-iform. In most species involucral bracts are
found at the base of it. These bracts (which are alluded to in the following pages as
tlie basal bracts) are usually three in number. Tliey are generally distinct from" each
other, but sometimes they are slightly united, so as to form a kind of involucral cup.
The receptacle in many species is contracted towards its base, and in some tliis contraction
is cari-ied to such an extent that a kind of false stalk is formed. This stalk-like
contraction must not however be confounded with the peduncle proper, by which, in
many species, the receptacle is attached to the axis; and as a fact the stalk Lay
invariably be distinguished from the peduncle proper by the position of the involucres
just referred to, which are attached at the apex of the peduncle proper, but at the
base of the pseudo-stalk. As regards situation, receptacles may occur in pairs in the
axils of the leaves (e.g. Urosi^ma), or they may be solitary in the same situation from
t h e abortion of one of the original pair- (e.g. Syncscia). They may also occm- in axillary
fascicles of three or more. In a large number of species (e.g. Emmorphe) the receptacles
are borne on tuberclcs {i.e. shortened leafless branehlets) from the larger branches or
f r om the stem; while in one set of species {Covdlia) the receptacles are bome on long,
sub-aphyllous branches, which, proceeding from the stem near its base, either trail
along the sm-face of the ground or bury themselves in the soil. In one very remarkable
species {F. Minahassae) the receptacles are collected in dense capitula, whicJi in turn are
arranged in long leafless branches wliich iU-oop towards, but hardly roach, the ground.
I n a few species fe.g. F. húpida) receptacles occm- both in the axils of the leaves and on
stem tubercles. In size, as in colour, the receptacle varies much, and excellent
specific characters are deiived from these differences.
The flowers, which are mostJy unisexuaJ. are situated on the inner walls of the receptacle.
They may be either sessile or pedioillate. In some species they are separated from
each other by scales or bracteoles, and in others by hairs, both of which appendages
INTEODUCTION. -y
appear to be analogous to the paleai that are found on the receptacles of many Compoiitw.
I n other species the flowers lie close together, unsoparated by any intervening appendages.
Five kinds of flowers are found in the genus, viz. male, pseudo-hermaphrodite, neuter,
fertile female, and gall flowers. The structure of each of these is ver y simple. The male
flowers consist of a perianth of from three to five pieces, which, although sometimes united,
are usually free. The perianth sometimes hardly covers the stamen or stamens; in other
cases it is lai'gc, inflated, and completely envelopes the stamen. In some species the
pieces of the perianth are thin and colourless, and not unfrequently hyaline; in others
they are of a red or dark-brown colour and opaque. In quite half the Indo-Malayan
species there is only a single stamen; in very many there are only two; wliile in only
a few are there so many as three. In shape the anthers are for the most part ovate or
elliptic, although some are very broad and almost rotund; they are always 2-celled
and have sutural deliiscence. Some are sessile or nearly so, and in very few is the filament
long. The attacliment of the anther to the filament is innate in most species; in a few,
however, it is adnate. In species with two stamens the filaments are often united for tlic
whole or pai't of theii- length, leaving the anthers however free.
Pseudo-hermaphrodite flowers occur in only a few species. Such flowei-s have a
perianth like the ordinary male flower, but along with the single stamen there is
present in them a pistil with completely formed style and ovary. I have, however, never
found one of these ovaries to contain a seed, but I have not unfrequently found one
containing a pupa.
Keuter flowers are found only in the few species forming the section Synmcia. They
are long-pedicillate and have a 3-leaved perianth, without any trace of either anther
or pistil.
Fertile female flowers havo a perianth not very different from that of the males,
but consisting in many cases of more pieces, and being more often gamophyllous.
I n the case where the pieces of the perianth are free, the individual pieces are sometimes
rather easily detached, and are very apt to be confounded with the bracteoles of the
receptacles in species where the latter exist. The perianth is usually much smaller tlian
tlie mature achene, and covers the latter very incompletely or not at all. In some cases
where the perianth is gamophyllous it forms a small cup, which surrounds only the
base of the ovary or its pedicel. It was in some such cases, where the perianth is
hyaline, that iliquel was led to believe that none existed; and hence his statement
about the perianth being absent in CovelUa. The pistil may be sessile, but it is
ver}' often pedioillate; the ovary is more or less ovoid or obovoid, with a teudenc)-
to be emarginate on the side at wliich the style is attached. It contains a single
pendulous ovule. The style is filiform, and is in most cases distinctly lateral or sub-terminal:
it rarely springs from the apex of the ovary. In length the style usually greatly exceeds
t h e ovary: it is usuall}^ smooth, but in a few species it is haiiy. The stigma, which