837 



FLOWER. 



FLOWER. 



838 



which does not immediately bear seed-buds, is called the Disc (Discus). 

 This may be situated beneath the rudiment of the fruit (Discus Hypo- 

 gy nus), and then may be flat, as in Potent ilia and Frayaria ; or cup- 

 shaped, as in Sota, Popttlus (mas), &c. This latter may be free 

 (Sola), or may be blended with the germen situated inside it (Pyrus) ; 

 or it may pass off from the middle of the (half-inferior) germen 

 (Discus Perigynus), as in many Myrtacea ; or, lastly, it may rise above 

 the (inferior) germen, and stand upon it (Discus Epigynus). Here it 

 is very rarely (or never ?) flat, but funnel-shaped, as in Godetia ; in the 

 form of a long tube, as in (Enothera ; or resembling a style, as in the 

 OrcMdace(e and A ri&tolochiacece. In all these cases, the foliar organs 

 of the flower may be situated in very different places. Usually, 

 indeed, they collectively form a zone around the edge of the flat or 

 concave discs ; then the discs may be said to correspond to as many 

 discs lying one above another as there are internodes implied by 

 the number of foliar organs. Frequently the true foliar organs stand 

 around the edge of the disc ; and upon its inner or upper surface the 

 gennens are arranged in one or more circles (as in Rosa, Punica, 

 Onagracece). More rarely the floral envelopes alone stand on the 

 border, while the stamens are then at a distance from them, upon an 

 internal prolongation of the disc, as in the Orchidacea:. 



The disc is by no means always regularly developed, but sometimes 

 enlarged at one side only, whereby the whole flower appears oblique, 

 thus in Reseda. The most remarkable structure ia in Pelargonium, 

 where the disc forms a cavity to one side of the peduncle, arid in 

 Tropceolmn, where the spur is formed solely by the disc. 



There are but few special observations to be made respecting the 

 structure of the internodes of the flower ; it is in general like that of 

 annual stems ; but it should be remarked that they often possess 

 fewer vascular bundles, and these of simpler development. The inter- 

 nodes (as also some of the foliar organs) within the flower, frequently 

 do not have the epidermis developed, but, instead of this, a delicate 

 soft cellular tissue, somewhat yellowish in colour, and often con- 

 taining a saccharine secretion, forms the investment of the surface 

 (Nectarium). 



It is very rarely that a flower consists of one part only, as in the 

 male flowers of Euphorbia, Lemna, and Wolffia, which are formed of 

 one foliar organ, the anther ; or the female flower of Tax us, which is 

 formed of one axial organ, the seed-bud. Usually more parts unite to 

 form a flower : thus the female flower of most of the Aracece consists 

 of one or more seed-buds, and a carpel surrounding them. The male 

 flower of the Salicactce consists of a scale-like disc and several stamens. 

 In the generality of cases, male and female organs are both present in 

 the same flower : they are seldom naked, as in Hippuris, but usually 

 surrounded by floral envelopes. 



In axillary flowers, those parts which are turned towards the 

 peduncle are termed the upper, and those turned towards the bract, 

 where it is present, the lower. Some plants exhibit the peculiarity 

 that the pedicel, until the time of the blooming, makes a half turn 

 (analogously to the twining stem), and it may be the true pedicel, as 

 in Calceolaria and some Orchidacea ; or the inferior germ, as in most 

 of the Orchidacea. By this curve, the upper parts of such a flower 

 (in those plants the lip) become apparently the under; and such 

 flowers are termed Flores Resupiiiati. The term is sometimes falsely 

 applied to those Orchidaeece in which no such twisting takes place, 

 but in which the lip stands regularly as the upper part of the flower, 

 as, for example, in Epipogium. 



The individual organs of the flower taken generally, according to 

 the common view, and known by collective names, may originally 

 consist either of one piece or of more than one : in the first case they 

 are partes monomers; ; in the second case partes di-, tri-, or polymera). 

 In the latter case the parts may be entirely separated and inde- 

 pendent of one another, or they may be grown together in various 

 ways. These coherent sets were formerly also called partes monomene. 

 De Candolle better termed them partes gamomene ; as, for example, 

 Hemerocallit = perianthium gamo- (mono-) phyllum, hexamerum ; 

 Salvia, corolla gamo- (mono-) pctala, peutamera ; Kola, coralla penta- 

 petala, Ac. 



The coherence occurs here in the same manner as in the stem- 

 leaves, but on account of the crowded position in the flower-bud, 

 much more frequently. It happens either that a single foliar organ 

 grows together by its edges into a tubular or cup-like organ, as for 

 example occurs frequently in the so -called monomerous floral 

 envelope (Bracteole) ; or that several foliar organs grow together by 

 their edges : this commonly affects all the edges of a circle of leaves, 

 but sometimes two edge* remain ununited, as with the calyx of 

 Gatiiana lutea. So, again, this process is usually simultaneous in 

 development at all the edges of a circle ; but it sometimes happens 

 very much later a, on two uppermost leaf-edges, whereby the single- 

 lipped forms arise, as in the corolla of Teucrium and the Sores ligulati 

 of the Compoiita ; or, 6, with each pair of leaf-edges at the side of the 

 leaf-circle, whereby the two-lipped forms (partes bilabiate) of descrip- 

 tive botany arise. Another kind of blending also occurs in the flower, 

 of which no example occurs in the stem-leaves, and ouly one in the 

 bracts and bracteoles, namely, the cupula of the Cupuliferce ; this is, 

 the blending together of two or more circles, as in the two circles of 

 the floral envelopes of many Jjiliaccir ; or in these and the two circles 

 of stamens, in the circle of petals and stamens, in the Labiade, &c, ; 



and in general in all flowers to which are ascribed stamina perianthio 

 vel corolla; (not calyci) inserta. 



The coherence of the stamens of one or more circles has been well 

 termed, since Linn;eus's time, fraternity (Adelphia) ; and, according to 

 the number of brotherhoods in a flower, Monadelphia, Diadelphia, 

 Polyadelphia. When the foliar organs of the flower are coherent, the 

 blended part is termed the Tube (Tubus Periauthii, Calycis, Corolla;, 

 &e.) ; the free parts, the Limb (Limbus) ; and the boundary of the two, 

 the Throat (Faux). One of the most striking examples of coherence, 

 which also has no analogue in the stem-leaves, is found in the blending 

 of the foliar organs of the flower at the point only, the union never 

 extending farther ; so that the foliar organs are connected above, but 

 free below, as in the corolla of the male flowers of Chamcedorea, 

 Casuarina, and in the androphore of Symphyonema montanmn (?). 



Abortion in the flower means that some part present in the rudi- 

 mentary condition is arrested during the development and gradual 

 perfecting of the flower, and thus at last retires from observation. 

 There is no other kind of abortion. So soon as the individual parts 

 of a flower become distinct members, the foliar organs appear arranged 

 around an ideal and real axis of the flower (the axial organs of the 

 flower), and in the rudimentary condition always regularly. Through 

 subsequent unequal development of the single parts, the flower fre- 

 quently becomes unsymmetrical, or, as it is called, irregular. This 

 irregularity is always such that the upper part of a flower becomes 

 developed differently from the under. Such irregularity very seldom 

 affects the germen, which almost universally remains regular even in 

 unsymmetrical flowers ; yet there are cases in which this is the only 

 symmetrical part, as in many of the Scrophidaracece, Acanthacece, and 

 Oryptocoryne spiralig. If the unsymmetrical flower, with or without 

 coherence of its parts, is divided into two halves, an upper and under, 

 developed in different ways, they are generally termed bilabiate ; but 

 if ouly one single foliar organ ia developed in an aberrant form, that 

 leaf acquires the name of Labellum, or Lip. Rare indeed are the cases 

 where the entire flower is unsymmetrical, as in Goodyera discolor. 



It is not possible to state in general terms the number of parts 

 which may unite to form a flower. We find of foliar organs alone 

 sometimes as many as fifty or sixty united in one flower. Certain 

 combinations, on the contrary, are rarely met with : no monomerous 

 flower possesses double floral envelopes. When the various parts of 

 the flower are present in large numbers, these arise universally in one 

 or more circles (Whorls) at the same height on the axis, and at the 

 same time. When circles containing members of equal number follow 

 in succession, the members of the one circle usually stand opposite 

 the interspaces between the members of the preceding circle (the 

 circles and their members alternating) ; they seldom stand precisely 

 before them (the circles and their members opposite). But it by no 

 means is to be assumed that the members of each circle are always of 

 equal number in a flower. The number of members often increases 

 up to the stamens, and thence diminishes ; it is rare for the circle of 

 the carpel to contain the greatest number, as in the Malopece and 

 Mali-acea;. The generality of monocotyledonous plants with perfect 

 individual flowers have regular homomerous circles through the entire 

 flower : in dicotyledonous plants thia is relatively rarer ; the outer- 

 most and innermost circles have usually fewer members. Again, 

 respecting the number of circles which follow one another, no general 

 statement of importance can be given. Seven different forms of foliar 

 organs may possibly exist in the same flower, namely, the epicalyx, 

 calyx, corolla, accessory corolla, the stamens, accessory stamens, and 

 the carpels ; but there is no flower in which all occur in conjunction. 

 All these foliar organs may be present in one or more circles, with 

 the exception of the epicalyx, in which there is no example of a double 

 circle. Perianth, calyx, corolla, accessory corolla, and carpels occur 

 in one, or more rarely in two circles. Stamenti may be present in one, 

 two, three, or possibly even four circles ; more circles than this are 

 not exhibited in the normal condition of the flower. If the number 

 is increased, which seldom happens except in stamens and carpels, as 

 in Ranunculacete and Dryadace<e, the Maynoliacea;, &c., they stand no 

 longer in circles but in a spiral. In monocotyledouous plants with 

 perfect individualised flowers, with the single exception of some 

 Scitaminacece, five trimerous circles of foliar organs of the flower 

 appear to be formed in those where a second circle of petals exists. 

 The greatest multiplicity of forms occurs in the dicotyledonous plants. 

 Lavatera, for example, has an epicalyx, calyx, corolla, stamens, aud 

 carpels in five circles, with increasing numbers of members ; those of 

 the calyx and corolla alone are equal. Gnidia virescent has periauth, 

 stamens, accessory stamens, and carpels, but in eight circles, which 

 are throughout composed of two members each. It ia by no means 

 neceasary that all the parts of a circle of floral foliar organa should be 

 ultimately developed in the same manner ; and many floral structures 

 which have hitherto been apparently inexplicable may probably, by 

 keeping this truth in mind and following out the history of the 

 development, be readily traced back to the original type. 



The duration of the individual parts of the flower is very various ; 

 the axial organs, so far as they support the rudiment of the fruit or 

 aid in its formation, persist naturally at least uutil the ripening of 

 the seed, then fall away with it; or if it becomes disengaged from 

 them, die away with the remainder of the plant. When axes bear 

 only male organs or flowers their duration ia different ; sometimes 



