i88i.] BOTANY FOR GARDENERS. • 129 



BOTANY FOR GARDENERS. 



NO. VI. — INFLORESCENCE, ifec. 



Inflorescence is the ramification of that part of the plant intended 

 for reproduction by seed, and the reproductive organs of plants are the 

 flowers. Extremely varied indeed are the forms of inflorescence, in 

 some cases simple, but in most cases compound. In the Tulip it is 

 simple, and the peduncle supports but one solitary terminal flower. 

 A raceme has an inflorescence in which the flowers are arranged singly 

 on distinct pedicels along a common axis, — ex.^ Wallflower, many of 

 the Leguminosae, such as common garden Pea and Glycine (Wisteria) 

 sinensis, Veronica (garden varieties). A spike difi'ers chiefly from a 

 raceme in having its individual flowers sessile — that is, they are not 

 supported by a stalk as in racemes^ but lie close upon the body that 

 supports it, — ex., the common Plantain. A compound spike consists 

 of a collection of spikes arranged in a racemose manner. A spikelet is 

 a term used exclusively in describing Grasses, signifying the small ter- 

 minal collection of florets. A corymb is a form of raceme, in which 

 the pedicels are gradually shorter as they approach the summit, result- 

 ing in a flat-headed inflorescence, — ex.. Candytuft. An umbel is an 

 inflorescence in which the flowers expand first at the base and last at 

 the end or centre {centripetcdly) , with stalks radiating from a common 

 point, — ex., British Umbelliferae, such as Hemlock, Parsley, Carrot. 

 A ci/me is a kind of inflorescence produced by the rays of an umbel 

 forming one terminal flower, and then producing secondary pedicels 

 from below it, the flowers opening first at the end and last at the base, 

 — ex., Chickweeds, Stichworts, common garden Laurustinus. A panicle 

 is an irregularly branched raceme, — ex., Bramble, Horse-chestnut. 



Usually, though not invariably, the corolla forms the most ornamen- 

 tal part of plants, the parts of which are termed petals, which are 

 extremely varied and numerous in form. In some the corolla or 

 petals are polypetalous — that is, each part is separate from the other : 

 those of the Ranunculus are polypetalous, and are regular in form, 

 shape, and size. All representative British orders of the division 

 ThalamifloriB have their petals polypetalous, including such orders as 

 Ranunculace^, Cruciferse, Violace^e, and Caryophyllaceas, the greater 

 portion of which contain regular flowers. Those of Violacese, and a 

 few others, including Fumariacese, have their flowers irregular. In 

 the common Primrose the flowers are gamopetalous, and still regular. 

 In some cases the flowers may be labiate, as in the Mints (Meuthas), 

 Deadnettles, (Lamiums), &c. ; calceolate, as in Cypripedium calceolus ; 

 campanulate, as in the Harebells (Campanulas) ; ringent, as in the 

 Linaria vulgaris ; papilionaceous, as in leguminous plants — Pea, Bean, 

 ifec. ; funnel-shaped, as in the Polyanthus and many others. Some 

 plants do not possess any petals or sepals whatever, but are included 

 in the division AchlamydeaB, which contains several of our native trees, 



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