The Elements of Botany Part 11

_Moncious_ (or _Monoicous_, i. e. of one household), when flowers of both sorts or s.e.xes are produced by the same individual plant, as in the Ricinus or Castor-oil Plant, Fig. 230.

_Dicious_ (or _Dioicous_, i. e. of separate households), when the two kinds are borne on different plants; as in Willows, Poplars, Hemp, and Moonseed, Fig. 231, 232.

_Polygamous_, when the flowers are some of them perfect, and some staminate or pistillate only.

[Ill.u.s.tration: Fig. 230. Unis.e.xual flowers of Castor-oil plant: _s_, staminate flower; _p_, pistillate flower.]

[Ill.u.s.tration: Fig. 231, staminate, and 232, pistillate flower of Moonseed.]

250. A blossom having stamens and no pistil is a _Staminate_ or _Male_ flower. Sometimes it is called a _Sterile_ flower, not appropriately, for other flowers may equally be sterile. One having pistil but no stamens is a _Pistillate_ or _Female_ flower.

[Ill.u.s.tration: Fig. 233. Flower of Anemone Pennsylvanica; apetalous, hermaphrodite.]

[Ill.u.s.tration: Fig. 234. Flower of Saururus or Lizard's-tail; naked, but hermaphrodite.]

251. =Incomplete Flowers= are so named in contradistinction to complete: they want either one or both of the floral envelopes. Those of Fig. 230 are incomplete, having calyx but no corolla. So is the flower of Anemone (Fig. 233), although its calyx is colored like a corolla. The flowers of Saururus or Lizard's-tail, although perfect, have neither calyx nor corolla (Fig. 234). Incomplete flowers, accordingly, are

_Naked_ or _Achlamydeous_, dest.i.tute of both floral envelopes, as in Fig. 234, or

_Apetalous_, when wanting only the corolla. The case of corolla present and calyx wholly wanting is extremely rare, although there are seeming instances. In fact, a single or simple perianth is taken to be a calyx, unless the absence or abortion of a calyx can be made evident.

[Ill.u.s.tration: Fig. 235. Flower of Mustard. 236. Its stamens and pistil separate and enlarged.]

[Ill.u.s.tration: Fig. 237. Flower of a Violet. 238. Its calyx and corolla displayed: the five smaller parts are the sepals; the five intervening larger ones are the petals.]

252. In contradistinction to regular and symmetrical, very many flowers are

_Irregular_, that is, with the members of some or all of the floral circles unequal or dissimilar, and

_Unsymmetrical_, that is, when the circles of the flower or some of them differ in the number of their members. (Symmetrical and unsymmetrical are used in a different sense in some recent books, but the older use should be adhered to). Want of numerical symmetry and irregularity commonly go together; and both are common. Indeed, few flowers are entirely symmetrical beyond calyx, corolla, and perhaps stamens; and probably no irregular blossoms are quite symmetrical.

253. =Irregular and Unsymmetrical Flowers= may therefore be ill.u.s.trated together, beginning with cases which are comparatively free from other complications. The blossom of Mustard, and of all the very natural family which it represents (Fig. 235, 236), is regular but unsymmetrical in the stamens. There are four equal sepals, four equal petals; but six stamens, and only two members in the pistil, which for the present may be left out of view. The want of symmetry is in the stamens. These are in two circles, an outer and an inner. The outer circle consists of two stamens only; the inner has its proper number of four. The flower of Violet, which is on the plan of five, is symmetrical in calyx, corolla, and stamens, inasmuch as each of these circles consists of five members; but it is conspicuously irregular in the corolla, one of the petals being very different from the rest.

[Ill.u.s.tration: Fig. 239. Flower of a Larkspur. 240. Its calyx and corolla displayed; the five larger parts are the sepals; the four smaller, of two shapes, are the petals; the place of the fifth petal is vacant. 241. Diagram of the same; the place for the missing petal marked by a dotted line.]

[Ill.u.s.tration: Fig. 242. Flower of a Monkshood. 243. Its parts displayed; five sepals, the upper forming the hood; the two lateral alike, broad and flat; the two lower small. The two pieces under the hood represent the corolla, reduced to two odd-shaped petals; in centre the numerous stamens and three pistils. 244. Diagram of the calyx and corolla; the three dotted lines in the place of missing petals.]

254. The flowers of Larkspur, and of Monkshood or Aconite, which are nearly related, are both strikingly irregular in calyx and corolla, and considerably unsymmetrical. In Larkspur (Fig. 239-241) the irregular calyx consists of five sepals, one of which, larger than the rest, is prolonged behind into a large sac or spur; but the corolla is of only four petals (of two shapes),--the fifth, needed to complete the symmetry, being left out. And the Monkshood (Fig. 242-244) has five very dissimilar sepals, and a corolla of only two very small and curiously-shaped petals,--the three needed to make up the symmetry being left out. The stamens in both are out of symmetry with the ground-plan, being numerous. So are the pistils, which are usually diminished to three, sometimes to two or to one.

255. =Flowers with Multiplication of Parts= are very common. The stamens are indefinitely numerous in Larkspur and in Monkshood (Fig. 242, 243), while the pistils are fewer than the ground-plan suggests. Most Cactus-flowers have all the organs much increased in number (Fig. 229), and so of the Water-Lily. In Anemone (Fig. 233) the stamens and pistils are multiplied while the petals are left out. In b.u.t.tercups or Crowfoot, while the sepals and petals conform to the ground-plan of five, both stamens and pistils are indefinitely multiplied (Fig. 245).

[Ill.u.s.tration: Fig. 245. Flower of Ranunculus bulbosus, or b.u.t.tercup, in section.]

256. =Flowers modified by Union of Parts=, so that these parts more or less lose the appearance of separate leaves or other organs growing out of the end of the stem or receptacle, are extremely common. There are two kinds of such union, namely:--

_Coalescence_ of parts of the same circle by their contiguous margins; and

_Adnation_, or the union of adjacent circles or unlike parts.

257. =Coalescence= is not rare in leaves, as in the upper pairs of Honeysuckles, Fig. 163. It may all the more be expected in the crowded circles or whorls of flower-leaves. Datura or Stramonium (Fig. 246) shows this coalescence both in calyx and corolla, the five sepals and the five petals being thus united to near their tips, each into a tube or long and narrow cup. These unions make needful the following terms:--

_Gamopetalous_, said of a corolla the petals of which are thus coalescent into one body, whether only at base or higher. The union may extend to the very summit, as in Morning Glory and the like (Fig. 247), so that the number of petals in it may not be apparent. The old name for this was _Monopetalous_, but that means "one-petalled;" while gamopetalous means "petals united," and therefore is the proper term.

[Ill.u.s.tration: Fig. 246. Flower of Datura Stramonium; gamosepalous and gamopetalous.]

[Ill.u.s.tration: Fig. 247. Funnelform corolla of a common Morning Glory, detached from its polysepalous calyx.]

_Polypetalous_ is the counterpart term, to denote a corolla of _distinct_, that is, separate petals. As it means "many petalled," it is not the best possible name, but it is the old one and in almost universal use.

_Gamosepalous_ applies to the calyx when the sepals are in this way united.

_Polysepalous_, to the calyx when of separate sepals or calyx-leaves.

258. Degree of union or of separation in descriptive botany is expressed in the same way as is the lobing of leaves (139). See Fig. 249-253, and the explanations.

259. A corolla when gamopetalous commonly shows a distinction (well marked in Fig. 249-251) between a contracted tubular portion below, the TUBE, and the spreading part above, the BORDER or LIMB. The junction between tube and limb, or a more or less enlarged upper portion of the tube between the two, is the THROAT. The same is true of the calyx.

260. Some names are given to particular forms of the gamopetalous corolla, applicable also to a gamosepalous calyx, such as

_Wheel-shaped_, or _Rotate_; when spreading out at once, without a tube or with a very short one, something in the shape of a wheel or of its diverging spokes, Fig. 252, 253.

_Salver-shaped_, or _Salver-form_; when a flat-spreading border is raised on a narrow tube, from which it diverges at right angles, like the salver represented in old pictures, with a slender handle beneath, Fig. 249-251, 255.

[Ill.u.s.tration: Fig. 248. Polypetalous corolla of Soapwort, of five petals with long claws or stalk-like bases.]

[Ill.u.s.tration: Fig. 249. Flower of Standing Cypress (Gilia coronopifolia); gamopetalous: the tube answering to the long claws in 248, except that they are coalescent: the limb or border (the spreading part above) is _five-parted_, that is, the petals not there united except at very base.]

[Ill.u.s.tration: Fig. 250. Flower of Cypress-vine (Ipoma Quamoc.l.i.t); like preceding, but limb _five-lobed_.]

[Ill.u.s.tration: Fig. 251. Flower of Ipoma coccinea; limb almost _entire_.]

[Ill.u.s.tration: Fig. 252. Wheel-shaped or rotate and five-parted corolla of Bittersweet, Solanum Dulcamara. 253. Wheel-shaped and five-lobed corolla of Potato.]

_Bell-shaped_, or _Campanulate_; where a short and broad tube widens upward, in the shape of a bell, as in Fig. 254.

[Ill.u.s.tration: Fig. 254. Flower of a Campanula or Harebell, with a campanulate or bell-shaped corolla; 255, of a Phlox, with salver-shaped corolla; 256, of Dead Nettle (Lamium), with l.a.b.i.ate _ringent_ (or gaping) corolla; 257, of Snapdragon, with l.a.b.i.ate _personate_ corolla; 258, of Toad-Flax, with a similar corolla spurred at the base.]

_Funnel-shaped_, or _Funnelform_; gradually spreading at the summit of a tube which is narrow below, in the shape of a funnel or tunnel, as in the corolla of the common Morning Glory (Fig. 247) and of the Stramonium (Fig. 246).

_Tubular_; when prolonged into a tube, with little or no spreading at the border, as in the corolla of the Trumpet Honeysuckle, the calyx of Stramonium (Fig. 246), etc.

261. Although sepals and petals are usually all blade or lamina (123), like a sessile leaf, yet they may have a contracted and stalk-like base, answering to petiole. This is called its CLAW, in Latin _Unguis_.

_Unguiculate_ petals are universal and strongly marked in the Pink tribe, as in Soapwort (Fig. 248).

[Ill.u.s.tration: Fig. 259. Unguiculate (clawed) petal of a Silene; with a two-parted crown.]

[Ill.u.s.tration: Fig. 260. A small Pa.s.sion-flower, with crown of slender threads.]