FI.OWKI:. 



they are cast off at a trae articulation, sometimes they remain upon the 

 parent plant, and gradually die away. The foliar organs of the flower 

 are equally various in their duration. Perianth, corolla, and accessory 

 corolla commonly perish soon after the perfecting of the flower ; cither 

 they are cast off by true disarticulation, or they wither upon the 

 parent plant. The epicalyz and calyx frequently share the fate of 

 the axial organs supporting the rudiments of the fruit ; the carpels 

 almost invariably. The carpels are rarely destroyed before the per- 

 fecting of the seed, as in Ltontice, and according to Robert Brown in 

 J'rliotantliti Tkrla. The stamens die away almost immediately after 

 the disperrion of the pollen ; either they are cast off, or they dry up 

 and die away within the flower. 



The terminology in use is as follows : Those parts which fall away 

 immediately, when their perfect formation is but scarcely completed, 

 are termed caducous or fugacious (partes coductc) ; those which endure 

 somewhat longer are termed, if they are cast off by duarticulation, 

 deciiluous (partes decidiiic) ; if they retain their position, and die by 

 gradual withering and drying up, marcescent (partes marcescentes) ; 

 those parts which remain long, still vegetating, are termed persistent 

 (partes penistentes) ; if they change their forms by further growth 

 they are termed excrescent (partes excrescentes). 



As among the floral envelopes are usually reckoned the perianth, 

 the calyx, and the corolla, we may also include here the epicalyx. 

 Under the term perianth, in its narrowest sense, only those foliar 

 organs fall which, at leant two in number, are applied closely to the 

 flower and upon one level ; so that all individual foliar organs on the 

 axis of the flower, which only inclose stamens or germens, may be 

 termed bracts. All these bracts have this in common, that they are 

 merely foliar organs peculiarly modified ; and consequently all the 

 peculiarities of form which occur in the latter naturally appear in the 

 former also. It is not often that the leaves of the floral envelopes 

 have great thickness ; they are almost always more or less flat But 

 the forms analogous to the pitchers or pouches are here frequent, 

 much more so than U the case with the stem-leaves ; and these are 

 termed, according to their various resemblances to objects, cup-shaped, 

 as in the lower petal of Polygala ; hood-like, as in the upper leaf of 

 the perianth of A con it tun ; and so on. If a long sac-like appendage is 

 fanned at the basis of a perianthial leaf expanded above, it is called 

 a spur (calcar), as in Orckit, Delphinium, Fumaria, &c. The formation 

 of the spur is frequently conjoined with the formation of a symme- 

 trical flower, where one upper or lower foliar organ forms a spur. 

 The flattened expanded form, which is connected with the axis by a 

 linear prolongation, frequently occurs in the sepals ( '). This expanded 

 surface is termed the limb or blade of the leaf (lamina) ; the narrowed 

 base is not termed petiole but claw (unguis). True articulation is 

 frequent between the floral envelopes and the axis, but it never occurs 

 in the continuity of these leaves (?) ; therefore there are no true com- 

 pound perianthial leaves, though a simply divided limb is frequent, 

 an the petals palmatifida in Reseda, the petala pinnatifida in Xckizo- 

 pelalum, Ac, An indication of true articulation may probably be 

 afforded in the separation of the upper part of the tube of the flower 

 in itirabilit, of the calyx of the Datura from the lower, and in some 

 (similar cases. 



True stipules are not met with in the floral envelopes, but appen- 

 dages analogous to the ligula appear, to which indeed a part of the 

 structure described as the corona belongs. As in the Narcistu* and 

 the Lychnii, the scales of the throat of the Boraijinacta; also belong 

 here. These parts are formed in very various fashions on the floral 

 envelopes, and such appendages are sometimes exhibited standing 

 upon the surface of the foliar organ, in three or more rows, one above 

 another. Almost all parts recognised as corona and accessory corolla 

 (paracorolla) belong here, in particular a part of those elegant forms 

 exhibited in the fitapeliateamnd the Pa*rijtoi-acr<e ; so also does a portion 

 of the so-termed nectaria, as, for example in the petals of Jtanunculia. 

 All these are mere dependent appendages of the foliar organs, which 

 re developed originally simple and flat, all these parts being produced 

 from them subsequently. Here also occurs the one-sided development 

 of a foliar organ : this is seen frequently in the petals of the Apocy- 

 nacea ( \'i*ca, fferium, and Cerbera). 



The collective form of one or more circles, whether coherent with 

 each other or not, is more accurately designated according to further 

 peculiarities, as tabular (tubulosum), bell-shaped (cauipanulatuin), 

 funnel-shaped (infundibuliforme), salver-shaped (hypocrateriforme), 

 rotate (rotatum), Ac. 



Five kinds of floral envelope* are easy to be distinguished. When 

 all the foliar organs are similarly or nearly similarly developed in n 

 circle of one evident form, colour, and structure, they are described 

 under the general name of perianth, the single organs of which are 

 called perianthial leaves. If in the floral envelopes of one flower we 

 can distinguish two circles differing in form, colour, and structure, 

 the outer is named the calyx, it* component organs being sepals ; 

 while the inner is termed the corolla, it* single parts petals. Then 

 if three circles of forms are distinguishable the outermost is called 

 the epicalyx, the leaves of which may be denominated phylla. 

 When between the simple or manifold floral envelopes and the 

 tamens other independent foliar organs occur which exhibit a 

 structure very imperfect and abnormal compared with the true 

 envelopes, these are called a paracorolla, of which it will be 



necessary to speak further on, among the accessory parts of the 

 flower. 



The Perianth consists, according to the preceding considerations, 

 of one or more circles of leaves, which are developed so as to be 

 similar in colour, form, and structure. The following series of its 

 forms may be more minutely characterised : 



The individual foliar organs are always expanded in a flattened 

 form, seldom divided into limb and claw, and, at least when they are 

 not coherent, usually oval or lanceolate. They may be green, as in 

 the male flower of Urticacta, or of various colours, as in ThymtHacece ; 

 they may be firm and solid, and that especially when green, as in 

 Klira<ji>act(t ; or of delicate texture, as in Ariilolochiacta ; or they 

 may be developed as delicate sapless scales (palesc), or bristles and 

 hair, as in the Typhacece and Cyperacta. The perianth is almost uni- 

 versally regular, rarely (in some Ranvnculacecc and Orchidacea) 

 symmetrical ; in these cases never (?) 2-lipped, but often with one lip, 

 as in the Orchidacea. This is then not unfrequently developed, 

 hollow (cucullatum in Aconitum, calcaratum in Orekidaeea), and it is 

 commonly the uppermost leaf of the perianth. Its foliaceous por- 

 tions may be free, as in Juncacae ; or coherent, as in Funtia, Hemtro- 

 callu, &c. ; they may consist of one circle, as in Urticacece ; or of 

 more, as in Liliacea. The ports are frequently blended with the 

 stamens : in the coherent perianth the tube is sometimes straight, as 

 in Narcittu* ; sometimes curved, as in Ariitolochia. The mouth is 

 mostly naked ; sometimes, but seldom, as is the case in Narciutu, 

 furnished with appendages which form a corona, which however ore 

 rare in the perianth, and in free foliar organs only (?) occur on the lip : 

 the inner circle often has a beard. 



The structure of Perianthial Leaves, is on the whole, that of very 

 simple leaves, which exhibit no specal peculiarities, particularly if 

 they are green. The ramifications of the vascular bundles are there- 

 fore simple ; the separation into an upper and under parenchyma layer 

 is seldom exhibited ; but the epidermis usually. In the coloured and 

 delicate parts the cells of the parenchyma contain colouring matter. 

 In general the parenchyma is very loose and almost spongy, with 

 homogeneous transparent fluid contents, and large intercellular cavi- 

 ties tilled with air; hence the white colour. The epidermis is less 

 developed in coloured leaves, and more resembles the structure of 

 epithelium; stoniates are sometimes present, especially upon the 

 under surface, but the epidermal cells of the upper surface are often 

 raised in shorter or longer papillx, which give the upper surface a 

 peculiar vclvut-like appearance. It U very frequent here to find the 

 secreted layer of the epidermis (cuticle) regularly and delicately 

 striated (aciculatus), which certainly contributes to heighten the 

 brilliancy of the colour, and perhaps, by its effect upon the rays of 

 light, to the production and modification of the peculiar tints. 



Occasionally, especially at the base of hollow parts, no epidermis is 

 produced at certain points, and the parenchyma assumes a peculiar 

 structure, to perform the function of secretion of a juice containing 

 much sugar ; as, for instance, the nectary at the base of the perianthial 

 leaves of Fritillaria, very various parts on the labellum of the 

 Orchidacea, Ac. In rare coses the texture is hard and almost woody 

 from the interspersion of many thickened porous parenchymatous 

 cells, as in the species of Sanlain and Dryandra (?). In paleaceous 

 perianths the spiral and other vessels are not found in the usually 

 simple vascular bundles, and in hair-like perianths even the vascular 

 bundles themselves are wanting. 



The Calyx only exists when a corolla occurs with it ; it therefore 

 can never be confounded with it. It is always the external of two 

 dissimilar sets of envelopes. Its series of forms very much resembles 

 those of the perianth; perhaps it is not so frequently delicate in 

 structure and colour, as in the Scitaminacca, Musacctr, Sutomacece, 

 Ranunculus, Tropirolum, Ac. Usually it consists of one circle of 

 sepals, more rarely of two (as in the Herberidacea). These sepals are 

 always very simple, oval, or lanceolate, seldom pinnatifid, very 

 frequently brood at the base and tapering to a point, or very small 

 (denies calycis obsoleti) ; sometimes they appear only as dry scales, 

 or as tufts of hair (the pappus of the Compotita). Appendages 

 seldom occur upon the sepals, but they are frequently of hollow or 

 concave form. The number of the sepals in each circle U in Mono- 

 cotyledons frequently three, more rarely four or two; in the 

 Dicotyledons it is most frequently five, but also two, three, or four, 

 and perhaps sometimes more. Coherence of the sepals with one 

 another may occur in every way, but never with the corolla and 

 stamens, nor with the germens ; that which is so called being quite 

 another condition. Both in free and in coherent sepals, regularity 

 and symmetry are met with ; the latter often exhibit the bilabiate 

 structures. 



That which has been said of the structure of the perianth applies 

 also to the calyx, only that here green foliaceous sepals are the 

 more frequent 



The Corolla, which only exists as the inner set of floral envelopes 

 accompanying a calyx, may be compared to a very delicate and 

 coloured perianth. No true corolla occurs perfectly green and 

 resembling the leaves; its series of forms is greater than that of 

 any other of the floral envelopes. In the Monocotyledons it presents 

 in general only simple, round, oval, or lanceolate leaves, very seldom 

 having claws. In the Dicotyledons the forms are infinite, ai are 



