xvin 
OUTLINES OF BOTANY. 
consideration, the real as well as the apparent number has now in most cases been 
agreed upon. 
131. The Placenta is the part of the inside of the ovary to which the ovules are 
attached, sometimes a mere point or line on the inner surface, often more or less thick- 
ened or raised. Placentation is therefore the indication of the part of the ovary to 
which the ovules are attached. 
132. Placentas are 
axile, when the ovules are attached to the axis or centre, that is, in plurilocular 
ovaries, when they are attached to the inner angle of each cell ; in unilocular simple 
ovaries, which have almost always an excentrical style or stigma, when the ovules are 
attached to the side of the ovary nearest to the style ; in unilocular compound ovaries, 
when the ovules are attached to a central protuberance, column, or axis rising up from 
the base of the cavity. If this column does not reach the top of the cavity, the pla- 
centa is said to be free and central. 
parietal, when the ovules are attached to the inner surface of the cavity of a one- 
celled compound ovary. Parietal placentas are usually slightly thickened or raised 
lines, sometimes broad surfaces nearly covering the inner surface of the cavity, some- 
times projecting far into the cavity, and constituting partial dissepiments, or even 
meeting in the centre, but without cohering there. In the latter case the distinction 
between the one-celled and the several- celled ovary sometimes almost disappears. 
133. Each Ovule (121), when fully formed, usually consists of a central mass or 
nucleus enclosed in two bag-like" coats, the outer one called primine, the inner one 
secundine. The chalaza is the point of the ovule at which the base of the nucleus is 
confluent with the coats. The foramen is a minute aperture in the coats over the 
apex of the nucleus. 
134. Ovules are 
orthotropous or straight, when the chalaza coincides with the base (36) of the 
ovule, and the foramen is at the opposite extremity, the axis of the ovule being straight. 
campylotropous or incurved, when the chalaza still coinciding with the base of 
the ovule, the axis of the ovule is curved, bringing the foramen down more or less to- 
wards that base. 
anatropous or inverted, when the chalaza is at the apex of the ovule, and the 
foramen next to its base, the axis remaining straight. In this, one of t he most frequent 
forms of the ovule, the chalaza is connected with the base by a cord, called the raphe, 
adhering to one side of the ovule, and becoming more or less incorporated with its 
coats, as the ovule enlarges into a seed. 
amphitropous or half -inverted, when the ovule being as it were attached laterally, 
the chalaza and foramen at opposite ends of its straight or curved axis are about equally 
distant from the base or point of attachment. 
§ 12. The Receptacle and Relative Attachment of the Floral Whorls. 
135. The Receptacle or torus is the extremity of the peduncle (above the calyx), 
upon which the corolla, stamens, and ovary are inserted. It is sometimes little more 
than a mere point or minute hemisphere, but it is often also more or less elongated, 
thickened, or otherwise enlarged. It must not be confounded with the receptacle of 
inflorescence (74). 
136. A Pish, or disc, is a circular enlargement of the receptacle, usually in the form 
of a cup (cupular), of a flat disk or quoit, or of a cushion ( pulvinate ). It is either 
immediately at the base of the ovary within the stamens, or between the petals and 
stamens, or bears the petals or stamens or both on its margin, or is quite at the ex- 
tremity of the receptacle, with the ovaries arranged in a ring round it or under it. 
137. The disk may be entire, or toothed, or lobed, or divided into a number of parts, 
usually equal to or twice that of the stamens or carpels. When the parts of the disk 
are quite separate and short, they are often called glands. 
138. Nectaries, are either the disk, or small deformed petals, or abortive stamens, 
or appendages at the base of petals or stamens, or any small bodies within the flower 
which do not look like petals, stamens, or ovaries. They were formerly supposed to 
