The origin of floral structures through insect and other agencies . Tdj, or at least is homologous with, the petiolar portion of the caljcine leaves (Fig.27). Phjllomes, however,are after all but modifiedportions of caulomes, andpetioles are still less de-partures than are bladesfrom the nature of anaxis; so that while insome cases one is inclinedto regard the tube asmore strictly axial, inothers it seem to be morehomologous with a sort offasciation of petioles. We shall see directlythat the receptacular tubeof Prumis contains thebasal portions of the cordsproper to the calyx andcorolla, so th
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The origin of floral structures through insect and other agencies . Tdj, or at least is homologous with, the petiolar portion of the caljcine leaves (Fig.27). Phjllomes, however, are after all but modifiedportions of caulomes, andpetioles are still less de-partures than are bladesfrom the nature of anaxis; so that while insome cases one is inclinedto regard the tube asmore strictly axial, inothers it seem to be morehomologous with a sort offasciation of petioles. We shall see directlythat the receptacular tubeof Prumis contains thebasal portions of the cordsproper to the calyx andcorolla, so that we mightregard the latter as, onthe one hand, axial cordspreparatory to formingthe perianth; or, on theother, periantbial cordsnot yet differentiated intopetioles. Similarly, in the caseof monocotyledonousflowers, as the Daffodil, since petioles are less dif- Fig. 26.—Pear with liypertrophied and sub-fasciatepetiules.. Fig. 27.—Fuchsia with foliaceous sepals andpetals (after Masters). THE RECEPTACULAR TUBE. 95 ferentiated from blades in this class than in Dicotyledons, tlie inferior ovary may be due to the combination of the pistilwith the united sheath-like portion of the perianth, which isprolonged above the summit of the ovary just as it is inFuchsia, though it is not so piolonged in the Snowdrop. Anatomy of the Receptacular Tube.—Tracing the courseof the fibro-vascular cords from the pedicel below the flower, say of Primus Lauro-cerasus, the common laurel, there will befound to be ten, corresponding to the sepals and petals.The cortical tissue and epidermis are continuous throughout, from the pedicel to the summit of the tube. It is well seenalso in the tapering end of a pear, from which the cortexgradually widens, while the fibro-vascular cords run verti-cally up the middle. Before the cords arrive at the borderof the free tube of the Laurel, they have given rise to thestaminal cords by choris