510 THE GARDENER. [Nov. 



plant, but so metamorphosed from the ordinary leaf-bud that it re- 

 quires some attentive study to understand it. It is either sessile or 

 placed on a simple stalk, called a peduncle, on the top of which is 

 the receptacle on which some of the floral organs rest (this peduncle 

 is sometimes curiously hollowed out, as in the flower of the Rose and 

 Apple, and in the Fig it contains the flowers), or it is placed on a 

 branched stalk called a pedicel. If we examine it, beginning at the 

 outside, we have first, at the base of the peduncle, a whorl of leaves 

 called bracts, not necessarily green (in Bougainvillea spectabilis, 

 coloured), of which there are several kinds, from the simple forms 

 to the more elaborate spathe of Arum ; or if it is at the base of a 

 pedicel, we shall have bracteoles or an involucre. Then come the 

 floral whorls, generally four in number, consisting first of the calyx 

 and its parts or pieces, called sepals (sepalline leaves), not necessarily 

 green (in the Fuchsia, coloured); then comes the corolla, its parts called 

 petals, also metamorphosed leaves : and here we must revert to the 

 discoveries of Mr H. C. Sorby of the different kinds of pigments in 

 leaf-structure, and notice that the law of continuity running through 

 the leaf-structure of every plant, wherever found, will hold good in 

 the corolla, and explain how pigments in the leaf may also show 

 themselves in the petals of the corolla; and one is not surprised 

 to hear that it has been said that the greater the metamorphosis 

 of leaf-structure, as in an irregular flower, the more variation of 

 colour and markings may be expected. (This may or may not be 

 so.) Then come, in our examination, the stamens, which are still 

 metamorphosed leaves (staminate leaves), each stamen consisting of 

 a stalk or filament with an anther on the top, one or more lobed, 

 supplied with pores or valves containing minute cells, often yellow, 

 generally in a free state, sometimes in company with others, some- 

 times stuck together, containing fluid protoplasm, called pollen, — 

 they are parent cells, not grains, as they are often called. The for- 

 mation of the free pollen cell — its structure and its behaviour in the 

 protrusion of the pollen tube, and its endless diversity of appearance 

 in the higher plants, easily seen under the microscope — will soon teach 

 the gardener that there is no chance work here, but that all is the 

 work of some master-mind. In the centre of the flower is the pistil, 

 consisting of stigma, style, and ovary, also formed of metamorphosed 

 (pistillar) leaves, or carpellary leaves or carpels, the edges of which 

 have been so folded and tucked inwards as to form the style, of which 

 there are many different forms ; and at its summit the stigma, formed 

 of cellular tissue, but without epidermis, whose office is to receive 

 the pollen cell, which, either by falling upon, or by the work of in- 

 sects, comes in actual contact with the stigma, and is soon followed 



