INTRODUCTION TO BOTANY. ; ix 
Imperfect organs are said to be abortive ; or rudimentary, if very much reduced in 
size and almost obliterated. 
68. A flower is 
dichlamydeous, when the perianth is in two distinct whorls. 
ydeous, when the perianth is in one whorl, or when calyx and 
corolla are so consolidated as to appear in a single piece. 
asepalous, when there is no calyx. 
apetalous, when there is no corolla. 
naked, when there is no perianth. 
hermaphrodite, or bi-sexual, when both stamens and pistil are present and 
perfect. 
male or staminate, when stamens, but no pistil, or only an abortive one, are 
moannehs 
present. 
female or pistillate, when there is a perfect pistil, but no stamens, or only 
abortive ones, present. 
neuter, when both stamens and pistils are imperfect or absent. 
barren or sterile, when it produces no seed. 
fertile, when it does produce seed. 
69. The flowers of a plant or species are said collectively to be 
wnisexual or diclinous, when the flowers are all either male or female. 
monoecious, when the male and female flowers are distinct, but on the same 
root. 
dioecious, when the male and female flowers are on distinct roots. 
polygamous, when male, female, and hermaphrodite flowers are variously 
mixed on the same plant. 
70. A head of flowers or capitulum is heterogamous, when male, female, and her- 
maphrodite, and neuter flowers, or some of them, are included in it ; homogamous, 
when all the flowers are of one kind and structure. A spike or head is androgynous, 
herr male and female flowers are mixed in it. (See Composite, Aroidee, Cyperacee, 
C. : 
71. As the scales of buds are leaves undeveloped or reduced in size, shape, and 
consistence, and bracts are leaves likewise reduced in size and occasionally altered 
in colour ; so the parts of the flower are considered as leaves still further altered in 
shape, colour, and arrangement round the axis, and often more or less combined 
with each other. ; 
_ 72, To understand the arrangement of the floral parts let us take a complete flower, 
in which all the parts are free from each other ; definite in number, i.e., always the 
Same in the same species ; and symmetrical or isomerous, i.€., when each whorl con- 
sists of the same number of parts. The flower of Flax (Linum), of Crassula, or of 
Oxalis, answers to this description : the two first consist of 4, the last-named of 5 
whorls of altered leaves, placed immediately one within the other. 
73. The Calyx forms the outer whorl. is parts are called sepals. — 
74. The Corolla forms the next whorl. Its parts, called petals, usually alternate 
with the sepals, i.e, the centre of each petal is immediately over the interval be- 
tween two se le RO ee es 
75. The Stamens form one or two whorls within the petals. If two, those of the 
outer whorl (the outer-stamens) alternate with the and are consequently oppo- 
site to the sepals ; those of the inner whorl (the enner-stamens) alternate with the 
outer ones, and are consequently opposite the petals. If there is but one whorl of 
stamens, théy most frequently alternate with the petals; sometimes (as in Rhamnee 
and Primulacee) they are opposite the petals and alternate with the sepals. _ 
- 76. The Pistil forms the innermost whorl. Its parts, called carpels, usually (when 
definite and isomerous) alternate with the inner row of stamens. 
77. In an axillary or lateral flower the upper parts of each whorl (sepals, petals, 
stamens, or pistil) are those that are next the main axis of the stem or branch ; the © 
parts those that are furthest from it ; the intermediate are said to be lateral. 
78. The number of parts in each whorl of a flower is expressed adjectively by the 
following numerals, derived from the Greek : 
mono-, di-, tri-, tetra-, penta-, hexa-, hepta-, octo-, ennea-, deca-, &c., poly-, 
lL, a8, 4, 5-, nv i-, 8-, 9 10-, many-, 
prefixed to a termination indicating the whorl referred to. 
