490 
PHANEROGAMS. 
cases of apparent dichotomy, there are in Angiosperms only a few cases of actual or 
apparent extra-axillary branching, which will be mentioned when discussing the 
characteristic features of this class. 
Phanerogams are distinguished from Cryptogams by an extraordinarily varied 
and complete metamorphosis of members bearing the same name ; and this is con- 
nected with the almost infinite variety in the mode of life, and the more marked 
differentiation of the physiological functions of these plants; and the same is the 
case with the differentiation of tissues, which in Phanerogams greatly exceeds even 
that of Ferns. In these respects also Gymnosperms assume an intermediate 
position between Cryptogams and the rest of Phanerogams. 
What has now been said will serve to explain on one hand the distinction between 
Vascular Cryptogams and Phanerogams, on the other hand the points in which they 
agree, and the affinity of the two groups in their main outlines. In order, however, to 
facilitate the comprehension by the student of the characteristics of the separate classes 
of Phanerogams which are now to be described, we must in the first place keep in 
view a few of their peculiarities, which have at present only been briefly touched upon, 
and attempt to settle the nomenclature, which has become to some extent obsolete 
and out of harmony with the most recent theories. 
The Flower, in the broadest sense of the term, is composed of modified foliar organs 
and of an axis which bears them. [The most highly modified leaves of the flower are 
the stamens and the carpels : these so-called ' sexual organs ' are really spore-bearing 
organs, comparable to the spore-producing leaves of the Vascular Cryptogams.] When 
the leaves which stand immediately beneath the sexual organs on the same axis diff'er 
from the rest of the leaves of the plant in their arrangement, form, colour, or structure, 
and are physiologically connected with fertilisation and its results, they are considered as 
belonging to the flower, and are termed collectively the Floral Leaves or Perianth. 
The separate flowers are distinguished from the Inflorescence by including, together 
with their sexual organs and perianth, only one axis, while the inflorescence is an axial 
system with more than one flower ^ Roper has termed the tout ensemble of the male 
sexual organs of a flower the Andr(ecium, that of the female organs the Gynoßceum. 
When a flower contains sexual organs of both kinds it is called hermaphrodite or bisexual; 
if it contains only male or only female sexual organs, and is therefore unisexual, it is termed 
diclinous; when flowers of both sexes occur on the same individual plant, the species 
is moncecious, when on different individuals it is dioscious. Usually the apical growth 
of the floral axis ceases as soon as the sexual organs make their appearance, and fre- 
quently even earlier ; the apex of the floral axis is then concealed, and is often deeply 
depressed in the centre of the flower ; but in abnormal cases (and normally in Cycas) the 
apical growth of the floral axis re-commences, again produces leaves, and sometimes 
even a new flower, and a Proliferous Flo'^ver is thus produced. The sexual organs 
and perianth of a flower are usually crowded (arranged in rosettes either spirally or 
in whorls) ; the part of the floral axis which bears them remains very short, no inter- 
nodes being in general distinguishable in it; and it not unfrequently expands into the 
form of a club or disc, or becomes hollow, and this part of the floral axis is called the 
Torus or Receptacle. In Coniferae and Cycadeae (occasionally also in Angiosperms), it 
is however sometimes elongated to such an extent that the sexual organs appear loosely 
arranged along an axis in the form of a spike. Beneath the receptacle the axis is mostly 
^ In some cases it is however difficult to distinguish between a flower and an inflorescence ; 
as in some Coniferse, and especially in EupJwrbia. (On the latter, see Warming in Flora, 1870, 
no. 25 ; Schmitz, do. 1871, nos. 27, 28; and Hieronymus, Bot. Zeitg. 1872, no. 12.) [E. Warming, 
Er Koppen hos Vortemaelken en Blomst eller en Blomsterstand, Köbenhavn 1S71.] 
