. Practical botany. Botany. 110 PRACTICAL BOTANY loe--. Pi( . 'â >'.). Diagrams to show struc- ture of an anther The flowers of monocotyledons and of dicotyledons very commonly have separate sepals and separate petals (Fig. 92). The sepals and petals are then said to be distinet. In the more specialized and higher families, both of monocotyledons and of dicotyledons, the receptacle often bears a tubular or cup- like outgrowth, and the peri- anth is borne upon this. In such cases the sepals, the pet- als, both, appear as if gro\A'n together into a tube, upon the free border of which are
. Practical botany. Botany. 110 PRACTICAL BOTANY loe--. Pi( . 'â >'.). Diagrams to show struc- ture of an anther The flowers of monocotyledons and of dicotyledons very commonly have separate sepals and separate petals (Fig. 92). The sepals and petals are then said to be distinet. In the more specialized and higher families, both of monocotyledons and of dicotyledons, the receptacle often bears a tubular or cup- like outgrowth, and the peri- anth is borne upon this. In such cases the sepals, the pet- als, both, appear as if gro\A'n together into a tube, upon the free border of which are seen teeth, or lobes, A-hich indi- cate the number of divisions of which the perianth is com- posed (Fig. 97).i Sympetalous corollas occur of many extraordmary forms, enabling them to aid in seed production. The only sueh co- rolla shown in this book is the CyiJiipi-iliiim of the Orchis family (Figs. l!81 and l^S2). union of stamens. A common form of stamen is that shown in Fig. 100, A, consisting of an enlarged portion called the anther, Ijorne by a slender stalk called the filament. AVlien the filament is lacking, the sta- men is said to be i<emle. Sometimes the filaments appear to be united, thus joinmg the stamens into one, two, or more 1 When the sepals are distinct the flower is said to be chorisepalous (sepa- rate sepals) ; when the petals are distinct, choripetalous. When the sepals or petals appear only as teeth or lobes on the margin of a tubular or cup-like outgrowth of the receptacle, the calyx is said to be synsepalous and the corolla sympetalous {syn signifies " together "). The terms gamosepalous and gamo- petalous are also used {gamos signifies "marriage" or "union"). .1, y(mnger stage, with four chambers or toe'//e«(?op) containing pollen mother cells dividing to fonn pollen grains; /;, Ku older stage in which the pollen grains (y <) are fully formed and each pair of locules is uniting to form a pollen sac, which will sp
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