INTRODUCTION. XV 



infundihuUform ov funnel -sliaped^ wlien the tube is cylindrical at the base, but en- 

 larged at the top 'm\o a more or less campanukf e limb, oi which the lobes often spread 

 norizontally. In this case the campnnulate part, up to the commencement of tlie 

 lobes, is sometimes considered as a portion of the tube, sometimes as a portion of tlie 

 hmb, and by some botanists again described as independent of either, under the name 

 01 throat {fauces). Generally speaking, liowever, in campanulnte, infuudibiiliform, or 

 other corollas, where the lower entire part passes gradually into the upper divided and 

 more spreading part, the distinction between the tube and the limb is drawn either at 

 the point where the lobes separate, or at the part where the corolla first expajids, ac- 

 cording to which is the most marked. 



105. Irregular corollas have received various names according to the more familiar 

 forms they have been compared to. Some of the most important are tlie 



lilahiate or ttvo-lipped corolla, when, in a four- or five-lobed corolla, the two or 

 three upper lobes stand obviously apart, like an upper lip^ from the two or three lower 

 ones or under Up, In OrchidecB and some other famihes the name of lip, or labellum^ 

 18 given to one of the divisions or lobes of the perianth. 



personate^ when two-li]iped, and the orifice of the tube closed by a projection from 

 the base of the upper or lower lip, called tx jmlate. 



Tingent^ when very strongly two-Upped, and the orifice of the tube very open. 



spurred^ when tlie tube or the lower part of the petal lias a conical hollow projec- 

 tion, compared to the spur of a coct ; saccate, when the spin- is short and round like a 

 httle bag ; gibbous, when projecting at any part into a slight swelling ; foveolate, when 

 marked in any part ^vith a slight glandular or tliickened cavity. 



restipinate or reversed, when a lip, sjxa-, etc., which in allied species is usually 

 lowest, lies uppermost, and vice versd, 



106, The above terms are mostly applied to the forms of mouopetalous corollas, hut 

 several are also applicable to those of polypctalous ones. Terms descriptive of the 

 special forms of corolla in certain Natural Orders, will be explained under those 

 Orders respectively. 



.107. Most of the terms used for describing the forms of leaves (39, 4-5) are also ap- 

 plicable to those of individual petals j but the flat expanded portion of a petal, cor- 

 responding to tlie blade of the leaf, is called its lamina, and (iie stalk, cori-esponding 

 to the petiole, its claw {unguis). The stalked petal is said to be iinguiculate. 



§ 10. The Stamens, 



grad 



itt genera], Stamens are very different in shape and aspect from leaves, sepals, or 

 petals. It is only in a theoretical point of view (not the less important in the study 

 ot the physiological economy of the plant) that they can be called altered leaves. 



109. This usual form is a stalk, called the filament, bearing at the top an anther 

 oivided into two pouches or cells. These anther-cells are filled with pollen, consisting 

 ot rninnte grains, usually forminrr a yellow dust, which, when the flower expands, is 

 scattered from an opening in each ceil. When the two cells are not closely contiguous 

 the portion of the anther that unites tlieni is called the connedlvum. 



110. The filament is often ^vant^n^, and the anther sessile, yet stiU the stamen ifl 

 perfect; but " * " '' ...«.,- . .:..» 



aoes not cont 

 (without 



'n|)ertection ia carried. Imperfect stamens are often called staminodia. 



111. In unsymmetrical flowers, the stamens of each whorl are sometimes reduced m 

 number below that of the petals, even to a single one, and in several Natural Orders 



^^7, fejnultiplied indefinitely. ,. , , 



U2 The terms monandrous and mlyandrous are restricted to flowers which Jiave^ 



^c^^ily but one stamen, or an indefinite number respectively. Where several stamens 

 ^_|mited into one, the flower is said to be synandrous. 



113. Stamens ai'e mi • i i^ • i, 



^onadelphoii^, when united by their filaments into one cluster. Tins cluster either 



c 3 



