OUTLINES OF BOTANY. xv 



§ 12. The Reci-ptncle and Relative AUachmenI of the Floral Wliorh. 



135. The Receptacle or toruis is the extremity of the peduncle (above the calyx), upon 

 which the oaroUa, 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 Disk, or disc, is a circular enlargement of the receptacle, usually in the form of a cup 

 (cupalar). 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 extremity 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 supply bees with their 

 honey, and the term is frequently to be met with in the older Floras, but is now deservedly 

 going out of use. 



139. When the disk bears the petals and stamens, it is frequently adherent to, and apparently 

 forms part of, the tube of the calyx, or it is adherent to, and apparently forms part of, the 

 ovary, or of both calyx-tube and ovary. Hence the three following important distinctions in the 

 relative insertion of the floral whorls. 



140. Petals, or as it is frequently expressed, flowers, are 



hypogynous {i.e. under the ovary), when they or the disk that bears them are entirely free 

 both from the calyx and ovary. The ovary is then described as free or superior', the calyx as 

 free or inferior, the petals as being inserted on the receptacle. 



perigynons {i.e. round the ovary), when the disk bearing the petals is quite free from the 

 ovary, but is more or less combined with the base of the calyx-tube. The ovary is then still 

 described as free or superior, even though the combined disk and calyx-tube may form a, deep 

 cup with the ovary lying in the bottom ; the calyx is said to be free or inferior, and the petals 

 are described as inserted on the calyx. 



epigynous {i.e. upon the ovary), when the disk bearing the petals is combined both with the 

 base of the calyx-tube and the base outside of the ovary ; either closing over the ovary so as 

 only to leave a passage for the style, or leaving more or less of the top of the ovary free, but 

 always adhering to it above the level of the insertion of the lowest ovule (except in a very few 

 cases where the ovules are absolutely suspended from the top of the cell). In epigynous flowers 

 the ovary is described as adherent or inferior, the calyx as adherent or superior, the petals as 

 inserted on or above the ovary. In some works, however, most epigynous flowers are included in 

 the perigynous ones, and a very different meaning is given to the term epigynous (144), and 

 there are a few cases where no positive distinction can be drawn between the epigynous and 

 perigynous flowers, or again between the perigynous and hypogynous flowers. 



141. When there are no petals, it is the insertion of the stamens that determines the difference 

 between the hypogynous, perigynous, and epigynous flowers. 



142. When there are both petals and stamens, 



in hypogynous flowers, the petals and stamens are usually free from each other, but some- 

 times they are combined at the base. In that case, if the petals are distinct from each other, 

 and the stamens are monadelphous, the petals are often said to be inserted on or combined with 

 the staminal tube ; if the corolla is gamopetalous and the stamens distinct from each other, the 

 latter are said to be inserted in the tube of the corolla. 



in perigynous flowers, t!ie stamens are usually inserted immediately within the petals, or 

 alternating with them on the edge of the disk, but occasionally much lower down within the 

 disk, or even on the unenlarged part of the receptacle. 



in epigynous flowers, when the petals are distinct, the stamens are usually inserted as in 

 perigynous flowers ; when the corolla is gamopetalous, the stamens are either free and hypogy- 

 nous, or combined at the base with (inserted in) the tube of the corolla. 



143. When the receptacle is distinctly elongated below the ovary, it is often called a gynobasis, 

 gynophore, or stalk of the ovary. If the elongation takes place below the stamens or below the 

 petals, these stamens or petals are then said to be inserted on the stalk of the ovary, and are 

 occasionally, but falsely, described as epigynous. Eeally epigynous stamens {i.e. when the 

 filaments are combined with the ovary) are very rare, unless the rest of the flower is epigynous. 



144. An epigynous disk is a name given either to the thickened summit of the ovary in 

 epigynous flowers, or very rarely to a real disk or enlargement of the receptacle closing over the 

 ovary. 



145. In the relative position of any two or more parts of the flower, whether in the same or 

 in different whorls, they are 



connivent, when nearer together at the summit than at the base. 

 divergent, when further apart at the summit than at tlie base. 



