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In this article we will discuss about the description and families of flowering plants.
Description of Flowering Plants:
Habit:
Herb, shrub, tree, trailer, creeper, twiner, climber, etc.
Life Span:
Annual, biennial or perennial.
Habitat:
ADVERTISEMENTS:
Mesophytic, hydrophytic or xeophytic.
Root:
Tap or adventitious root system, any speciality or modification.
Stem:
Herbaceous or woody, solid or fistular, cylindrical, angular or flattened, any modification like tendril or thorn, surface (smooth, hairy, glabrous, rough or prickly).
Leaves:
Simple or compound, type if compound, deciduous or persistent, type of phyllotaxy like spiral (alternate), opposite or whorled, sessile, subsesile or petiolate, stipulate or exstipulate, ligulate if ligule present, shape, margin, apex, venation (umcostate or multicostate, reticulate or parallel), modification if any.
Inflorescence:
ADVERTISEMENTS:
Type— solitary, simple or compound raceme, cyme, mixed or special.
Flower:
Bracteate or ebracteate; bracteolate or ebracteolate; pedicellate (pedicel if hairy, coloured or jointed), sub-sessile or sessile; complete or incomplete; perfect (hermaphrodite), imperfect (unisexual, staminate or pistillate) or neuter; regular or irregular; actinornorphic, zygomorphic or asymmetrical; bimerous, trimerous, tetramerous, pentamerous or heteromerous; cyclic, hemicyclic (spirocyclic) or spiral; hypogynous, perigynous or epigynous; any peculiar form like papilionaceous, cruciform, bilabiate, etc.; colour; scent if any.
Calyx:
Number; polysepalous or gamosepalous (toothed, fid or partite); description of whorls if more than one. Outline of individual sepals if free; form of calyx if united; aestivation valvate, twisted or imbricate; description of odd sepal if anterior; special structure if any; green or petaloid; caducous, deciduous or persistent; inferior or superior.
Corolla:
Number; polypetalous or gamopetalous (toothed, fid or partite); description of whorls if more than one, outline of individual petals if free; form of corolla if united; aestivation valvate, twisted or imbricate; description of odd petal if posterior; special structures like spur, veins, glands, if any; superior or inferior.
Perianth:
Describe like calyx and corolla, substituting the word sepalous or petalous with phyllous. The same terms are also used in the case of epicalyx which is described before the calyx when present.
Androecium:
Number of stamens or numerous; polyandrous, adelphous (monadelphous diadelphous or polyadelphous), syngenesious (synantherous) or synandrous; number of Whorls If more than one; arrangement of Stamens in relation to petals like antipetalous (antiphyllous in case of perianth) or alternipetalous (altemiphyllous in case of perianth), if in two whorls diplostamenous or obdiplostamenous, epipetalous (epiphyllous in case of perianth); any speciality of filament; any speciality of anther; monothecous or bithecous; fixation of anther and its mode of dehicence; inferior or superior.
Gynaecium:
Number (mono-, bi-, tri-, penta-, or poly-carpellary); apocarpous or syncarpous (if the number is more than one); ovary superior or inferior; any characteristic of the ovary visible from outside; number of ovary chambers (unilocular, bilocular, trilocular, tetralocular, pentalocular or multilocular); placentation (marginal, parietal, axile, free central) basal or superficial, number of ovules per loculus; type of ovules; any characteristic of style (free or united long or small, terminal lateral or gynobasic, filiform, curved, etc.); stigma (minute or capitate, fid or lobed, surface smooth, rough or hairy); nectaries, disc and stalk below the ovary if present.
Fruit:
Type of fruit, size, shape, number of seeds.
Seed:
Endospermic or non-endospermic; monocotyledonous or dicotyledonous shape and size.
Vertical Section:
ADVERTISEMENTS:
In a vertical section the flower is cut vertically in the anteroposterior or median plane The vertical section shows the shape and relative size of the different types of floral organs, placentation in the vertical plane, the rough number of ovules per chamber, insertion of floral parts on the thalamus, fusion of different parts, fixation of anthers, etc.
Floral Formula:
It is symbolic representation of floral symmetry, presence or absence, number, cohesion and adhesion of various parts.
The floral formula tells us about bracteate or ebracteate nature and the symmetry of the flower, its sexuality, number and union of sepals, petals, stamens and carpels, the insertion of stamens either on the thalamus or fusion with the petals (or perianth) and the superior and inferior position of the gynaecium.
They are all represented by symbols which are as follows:
The numbers of parts are written at the right foot of the symbol. If the number is up to five or so, actual number of parts is written. If the number is much more, the sign of infinity ‘∞’ is used.
More than one whorl or group of a type of floral organs is represented by using the sign plus and writing the actual number of parts in each group or whorl, e.g., K5-(5 sepals), K2+2-(4 sepals in two groups or whorls of two each), A∞ — (indefinite or numerous stamens).
If the floral parts of a series are united in one or more groups, the number of parts is written within brackets, e.g., K(5) (Calyx number 5, gamosepalous), A(9) + 1 (Androecium diadelphous, one group containing 9 fused stamens, the other group having single free stamen).
The epipetalous or epiphyllous condition of androecium is represented by an arc which joins, androecium with the corolla or perianth as the case may be, e.g., С – A or P – A.
ADVERTISEMENTS:
Superior ovary or gynaecium is indicated by a bar below the number of carpels while the inferior condition is represented by a bar or horizontal line above the number of carpels, e.g., (Gynaecium bicarpellary, syncarpous, superior); (Gynaecium bicarpellary, syncar pous, inferior).
Some of the floral formulae of the common flowers are as follows:
Ranunculus. Ebr 
(Ebracteate, Actinornorphic, Bisexual; Calyx- 5, free; Corolla- 5, free; Androecium numerous, free; Gynaecium— polycarpellary, apocarpous, superior).
Brassica. 
(Ebracteate; Actinornorphic, Bisexual; Calyx- 4, polysepalous, in two whorls of two each; Corolla-4, polypetalous, cruciform; Androecium-6, polyandrous, tetradynamous in two whorls, one with two, the second with four; Gynaecium- Bicarpellary, syncarpous, superior).
Floral formula has its own limitations. It does not give information about:
(i) Asestivation
(ii) Relationship with members of the same or different series
(iii) Placentation
(iv) Chambers of the ovary
ADVERTISEMENTS:
(v) Nectaries, etc.
Floral Diagram:
The floral diagram is a diagrammatic representation of theoretical transverse section and ground plan of a floral bud in relation to the mother axis which lies at the posterior side.
It is highly illustrative and describes most of the features of the flower and its parts like symmetry, regular or irregular, sexuality, number of the floral parts of each type, fusion among the similar parts (cohesion or connation) and with dissimilar parts (adhesion or adnation), aestivation of the floral parts, relation between the different floral organs, bithecous or monothecous nature of anthers, placentation, presence of nectaries, disc below the ovary, etc.
The mother axis is shown as a dot; sepals and petals are illustrated by arcs; the arcs of sepals have sharp point on the outer middle region while the arcs of petals are shown as smooth and solid; bract is shown by an arc on the anterior side, while bracteoles by arcs on the sides.
Stamens by double kidney shaped symbol (bithecous anther) and single kidney shaped symbol (monothecous anther); the gynaecium is shown as is observed in a transverse section. The fusion of the various parts is represented by suitable interconnecting lines. Usually the basal position of the floral parts is shown in the floral diagram.
ADVERTISEMENTS:
How to draw a Floral Diagram:
Represent the mother axis by a dot. Draw a few faint circles below it depending upon the number of different floral organs. If the flower is bracteates draw an arc towards the anterior side, outside the circles.
Now press the flower to the mother axis and note whether the mother axis lies opposite a sepal, petal or tepal. Draw the odd sepal by an arc at the posterior or anterior side depending upon its relation with the mother axis. Note the number of whorls of sepals and their number in each whorl.
Accordingly divide the outer circle (or circles) into parts and draw the arcs. If the sepals are fused, join the adjacent arcs by small triangles. If free, note the aestivation and show the overlapping of the margins. Draw petals in the inner whorl (or whorls). Usually the petals alternate with the sepals.
The stamens are represented by the symbols of their anthers in one or more circles depending upon the condition present in the flower. The fused stamens are shown by joining the symbols with solid lines.
The position of stamens vis a vis the petals or innermost perianth whorl should be carefully observed and maintained. The epipetalous or epiphyllous condition is shown by joining the symbols of stamens with petals or tepals either in the middle or in alternate position (in between two). Generally the stamens alternate with the petals.
The gynaecium is shown in the centre of the floral diagram. The apocarpous polycarpellary gynaecium is shown by double-lined circles in the centre according to the number of carpels present.
Their individual appearance in a transverse section is copied. In the case of syncarpous pistil, the transverse section of the ovary is drawn. Nectaries and other structures are drawn according to their position by suitable lines.
Families of Flowering Plants:
Dicotyledonae:
Family Fabaceae (papilionaceae):
(Subfamily Papilionoideae of Leguminosae):
Class— Dicotyledoneae, Subclass— Polypetalae, Series— Calyciflorae, Order— Rosales.
It includes 420 genera and 7000 species, with 754 in India.
Habit:
Herbs (e.g., Melilotus), shrubs (e.g., Tephrosia), climbers (e.g., Pisum, Lathyrus), twiners (e.g., Lablab) and trees (e.g., Dalbergia) found in mesophytic, xerophytic or halophytic habitats. Aeschynomene is aquatic.
Root:
Tap root system, much branched, nodulated or tubercled. Nodules contain nitrogen fixing bacteria of the genus Rhizobium.
Stem:
Herbaceous or woody, erect, twining (e.g., Lablab) or climbing (e.g., Pisum), stem branches are modifed into thorns in Alhagi pseudalhagi (= A. maurorum, Camel Thom, vern. Jawasa), solid or fistular, cylindrical or angular, may be hairy.
Leaves:
Cauline and ramal, alternate (rarely opposite or whorled), rarely simple (e.g., Crotalaria), generally pinnate compound, stipulate, stipules foliaceous in Lathyrus aphaca (Wild Pea), leaf base pulvinate, leaves (e.g., Lathyrus aphaca) or leaflets (e.g., Pisum sativum, Lathyrus odoratus) modified into tendrils, two lateral leaflets of Telegraph Plant (Desmodium motorium or D. gyrans) show autonomous movements.
Inflorescence:
Raceme, spike or rarely solitary.
Flower:
Bracteate or ebracteate, rarely bracteolate (e.g., Arachis), pedicellate or sessile, complete, perfect, irregular, zygomorphic, papilionaceous, perigynous or occasionally hypogynous.
Calyx:
5, gamosepalous, usually campanulate, lobes unequal, rarely tubular (e.g., Cyamopsis), aestivation imbricate, odd sepal anterior, may be persistent, inferior.
Corolla:
5, polypetalous, aestivation descending or vexillary imbricate, papilionaceous (butterfly-shaped) with five unequal petals posterior largest petal called standard or vexillum which overlaps two smaller lateral petals called wings or alae, the latter overlap a boat shaped structure called keel or carina which is formed by the two anterior petals fused lightly on the anterior side, lateral and anterior petals are scale-like in Erythrina indica (Indian Coral Tree).
Androecium:
10, usually diadelphous (1 + 9 in Lathyrus, 5 + 5 in Aeschynomene) or monadelphous (9 in Dalbergia, 10 in Arachis and Erythrina indica), rarely free (e.g., Sophora), nectar glands often present on the inner bases of filaments, dehiscence longitudinal, inferior.
Gynaecium:
Monocarpellary, ovary superior unilocular with marginal placentation, ovules many in two alternate rows, style bent, stigma simple or capitate.
Fruit:
Legume or lomentum.
Seed:
With or without scanty endosperm.
Floral Formula:
Diagnostic Characters:
(1) Presence of nodulated roots.
(2) Inflorescence racemose.
(3) Perigynous flowers.
(4) Flower zygomorphic and papilionaceous.
(5) Calyx 5, gamoespalous with odd sepal anterior
(6) Corolla 5, petals unequal and differentiated into standard, 2 alae and a keel or carina made up of two partially fused petals. The petals are arranged in descending imbricate fashion.
(7) Androceium commonly diadelphous (1 + 9 or 5 + 5) or monadelphous (10 or 9).
(8) Gynoecium monocarpellary, ovary unilocular with marginal placentation.
(9) Fruit a legume or lomentaceous pod.
Economic Importance:
1. Food (Pulses):
A number of legumes or pulses are obtained from fabaceae (papilionoideae) — Broad bean (Vicia faba, vern. Bakla), Sword Bean (Canavalia gladiata, vern. Bara Sem), Soyabean (Glycine max), Kidney Bean (Phaseolus vulgaris, vern. Farazbin), Cowpea (Vigna unguiculata = V. sinensis, vern. Lobia, Chholia), Butter or Lima bean (Phaseolus luntas, vern. Sem, Lobia), Lablab (Lablab purpureus Dolichos lablab vern. Sem), Pea (Pisum sativum), Gram (Cicer arietinum), Lentils (Lens culinaris — L. esculenta, vern. Masur), Green Gram (Vigna radiata = Phaseolus radiatus = P. aureus, vern. Mung), Black Gram (Vigna or Phaseolus mungo, vern. Urd), Mat Bean (Vigna aconitifolia = Phaseolus aconitifolius, vern. Moth), Pigeon Pea (Cajanus cajan, vern. Arhar).
2. Fodder:
Alfalfa (Medicago sativa, vern. Lusan), Indian Clover (Melilotus indica, vern. Senji), Guar (Cyamopsis tetragonaloba), Berseem (Trifolium alexandrium) and Shaftal or Shatala (Trifolium resupinatum).
3. Oils:
They are extracted from seeds of Arachis hypogea (Groundnut or Peanut) and Glycine max (Soybean). Roasted groundnut seeds are eaten.
4. Soil Fertility:
Nodule bearing papilionaceous plants increase nitrogen content of the soil. Therefore, they are used in crop rotation and green manuring, e.g., Crotalaria, Sesbania, Cyamopsis.
5. Fibres:
They are obtained from the stems of Crotalaria juncea (Sunn Hemp) and Sesbania species. The fibres are used in making cordage, sacks, nets, tissue paper, mats, canvas, etc.
6. Dyes:
Formerly indigo was obtained from the leaves of Indigofera tinctoria and I. sujfruticosa. The leaves contain a colourless chemical which on exposure to air turns bluish. A blood red dye is got from the wood of Pterocarpus santalinus (Red Sandal Wood). A dye is also obtained from Dalbergia species.
7. Gum:
Cyamopsis tetragonaloba yields guar gum which is employed in pharmaceuticals, explosives, ceramics, dyes, textiles, paper, plastics and photography. Gum is also secreted by Butea monosperma and Astragalus gummifer. It has medicinal use.
8. Medicines:
(i) The roots of Glycyrrhiza glabra (Liquorice, vern. Mullatthi) are used as demulcent, expectorant and in treating gastric ulcers. Their extract is also used to flavour medicines and tobacco.
It is added to chewing gum for flexibility, chocolates and candies to stabilise fat. For a similar purpose it can be added to shoe polishes and in etching solution for photomicrographic work. Glycyrrhizin, a glycoside of the root, is 50 times sweeter than sugar,
(ii) The seeds of Butea monosperma (Flame of the Forest, vern. Dhak) have antifungal and anthelmintic properties,
(iii) Seeds of Psoralea corylifolia (vern. Babchi) are anthelmintic, diuretic and capable of curing skin diseases including leucoderma.
(iv) Fresh leaf juice of Abrus precatorius (Jeweller’s Weights, Ratti) is useful in Fig. 5.138. Lathyrus odoratus, treating leucoderma.
(v) Juice of flowers of Sesbania grandiflora improves eye sight.
9. Cork:
It is obtained from Aeschynomene aspera (Indian Cork, vern. Sola).
10. Jeweller s Weights:
The seeds of Abrus precatorius (a climber) are employed as weights by jewellers.
11. Timber:
Dalbergia sisso (Sisso), Dalbergia latifolia (Indian Rosewood) and other species, Pterocarpus marsupium (Indian Kino), Butea monosperma (vern. Dhak). 12. Ornamentals. Lathyrus ordoratus (Sweet Pea), Clitoria ternata (Butterfly Pea), Colutea, Lupinus.
Type:
Lathyrus odoratus. (Sweet Pea, Fig. 5.138)
Inflorescence:
A few flowered long penduncled axillary raceme.
Flower:
Bracteate, ebracteolate, pedicellate, complete, perfect, irregular, medianly zygomorphic, pengynous, tetracyclic, pentamerous (except in gynaecium), papilionaceous, variously coloured, sweet smelling.
Calyx:
Five, gamosepalous (5-partite), campanulate (oblique), free lobes unequal, odd sepal anterior, hairy, persistent, green, inferior.
Corolla:
Five, polypetalous, papilionaceous consisting of a large posterior petal called standard or vexillum, two lateral petals named wings or alae and two anterior petals which are free at base but are fused together at the upper anterior edges to form a boat shaped structure called keel or carina, the keel encloses the essential organs, aestivation descending imbricate, petals clawed, colour various, inferior.
Androecium:
Ten, diadelphous, nine united by the lower half of their filaments to form an incomplete tube around the pistil, tenth posterior stamen free, anthers bithecous, basifixed, dehiscence longitudinal and introrse, filaments nectariferous in their basal regions, inferior.
Gynaecium:
Monocarpellary, ovary superior, flattened, elongated, hairy, unilocular, placentation marginal with many ovules present in two alternating rows, shortly stalked, i.e., borne on a short gynophore, style at an angle to the ovary, slightly flattened and hairy, stigma terminal and hairy.
Fruit:
Legume.
Family Soianaceae (Potato Family):
Classification:
Class— Dicotyledoneae. Subclass— Gamopetalae. Series— Bicarpellatae. Order Polemoniales.
Soianaceae has 90 genera and about 2000 species, out of which about 60 are represented in India. The plants occur widely in subtropical, tropical and temperate regions.
Habit:
Herbs, shrubs, a few’ trees (e.g., Solanum grandiflorum or Potato Tree) or climbcr (e.g., Solanum jasminoides or Potato Vine).
Root:
Tap.
Stem:
Erect, rarely climbing (e.g., Solatium jasminoides) or prostrate (e.g., Solanum surattense), herbaceous or woody, solid or listular, glabrous hairs or prickles often present, stem tubers occur in Solanum tuberosum (Potato), prickly in Solanum surattense.
Leaves:
Cauline and ramal, alternate in vegetative region and becoming subopposite in the floral region, exstipulate, sessile or petiolate, hairy, simple lobed or pinnately divided, pinnatisect in Tomato, venation unicostate reticulate, variegated in Solanum jasminoides.
Inflorescence:
Axillary or extra axillary helicoid or umbellate cyme, rarely solitary axillary (e.g., Petunia) or terminal (e.g., Datura).
Flower:
Ebracteate or bracteate, pedicellate, complete, perfect, regular, actinornorphic, rarely zygomorphic (e.g., Salpiglossis, Schizanthus), hypogynous, pentamerous in the outer three whorls, cyclic.
Calyx:
5, gamosepalous campanulate or tubular, persistent, accrescent (enlarging in fruit, e.g., Physalis, Withania,), aestivation valvate, hairy, inferior.
Corolla:
5, gamopetalous, variously shaped, campanulate, tubular infundibuliform, rotate, bilabiate in Schizanthus, plicate or folded like a fan in the bud, aestivation valvate inferior.
Androecium:
5, rarely 4, (e.g., Salpiglossis) or 2 (Schizanthus), free, epieptalous, often unequal, anthers bithecous, basifixed or dorsifixed, dehiscence longitudinal (e.g., Petunia) or porous (e.g., Solanum), inferior.
Gyaneeium:
Bicarpellary, syncarpous, ovary superior, carpels placed obliquely, generally bilocular (2-4 locular in Tomato, 4-locular in Datura due to false septa), placentation axile, ovules many in each loculus, placentae swollen, a nectariferous disc or lobes may be present, stigma capitate or lobed.
Fruit:
A many seeded berry (e.g., Tomato) or capsule (e.g., Datura).
Seed:
Endospermic with straight or curved embryo.
Diagnostic Characters:
(1) Aerial parts hairy.
(2) Bicollateral vascular bundles in the stem.
(3) Leaves alternate in the vegetative region but sub-opposite in floral region.
(4) Calyx 5, gamosepalous, persistent.
(5) Corolla 5, gamopetalous, often plicate in bud.
(6) Androecium 5, polyandrous and epipetalous.
(7) Gynoecium bicarpellary and syncarpous.
(8) Ovary placed obliquely.
(9) Placentation axile with swollen palcentae.
(10) Fruit berry or capsule.
Economic Importance:
1. Vegetables:
Potato (Solanum tuberosum) and Tomato (Lycopersicon lycopersicum= Lycopersicum esculentum) are the most common articles for cooking. Vegetables are also obtained from Brinjal (Solanum melongena) and Bell Pepper (Capsicum frutescens var. grossum, vern. Shimla Mirch).
2. Fruits:
The fruits of some Physalis species (e.g., P. peruviana, Gooseberry, vern. Rasbhari) are edible
3. Spices:
Chillies form the common spice. They are the fruits of Capsicum frutescens or C. annuum.
4. Tobacco:
It comes from the dried and cured leaves of Nicotiana tabacum and N. rustica. Tobacco is considered to be fumigatory, chewed, smoked or snuffed. Tobacco is intoxicant and stimulant but is habit forming and increases the incidence of heart trouble, lung cancer, and gum cancer, impotency in males and infant deformities in smoking mothers.
5. Medicines:
Atropa belladona (Deadly Nightshade, vern. Suchi) and A. acuminata (vern. Angurshafa) yield belladona for relieving pain externally, cough and excessive perspiration internally and atropine for dilating pupil.
Atropine sulphate stimultes perspiration and decreses sercretion from nose, mouth and bronchial regions. Henbane (Hyoscyamus niger, vern. Khurasani Ajwain) yields a sedative while Datura stramonium (Jimson Weed) gives an alkaloid called stramonium for relaxing bronchial muscles.
Roots of Withania somnifera (Ashwagandha) are used to cure rheumatism and general weakness. Fruits of W. coagulens (which are commonly used in preparing cheese) are useful in liver complaints and asthma.
Different parts of Solanum surattense (= S. xanthocarpum. vern. Kandiali, Mamoli) are used for curing cough, asthma, bronchitis, fever and leucoderma. Water left after boiling Potato tubers is supposed to cure skin bums and pimples.
6. Ornamentals:
A number of plants are grown as ornamentals, e.g., Petunia, Schizanthus (Butterfly Flower), Cestrum nocturnum (Night Jasmine), Brunfelsia hopeana (Yesterday today tomorrow). Datura, etc.
Type 1. Solanum nigrum (Black Nightshade, vern. Mako or Makoh, Fig. 5.139).
Inflorescence:
Extra axillary, 5-8 flowered scorpioid cyme called rhipidium. The extra axillary position is formed due to the union of peduncle with the stem for some distance beyond the axil.
Flower:
Ebracteate, ebracteolate, complete, perfect, regular, actinomorphic, cyclic, pentamerous in the outer three whorls, hypogynous, white.
Calyx:
5, gamosepalous (5-fid), campanulate, green, slightly hairy, persistent, inferior.
Corolla:
5, gamopetalous (5- partite), rotate, white, inferior.
Androecium:
5, polyandrous, altemipetalous and epipetalous, isostemonous, filaments short and hairy at the base, anthers large, bithecous, basifixed, yellow, crowded to form a cone around the style, dehiscence by apical pores, inferior.
Gyaneeium:
Bicarpellary, syncarpous, carpels (ovary) placed obliquely, ovary superior,bilocular, placentation axile, placentae swollen, many ovules in each loculus, style long, twisted and hairy at the base, stigma green bifid and capitate.
Fruit:
Berry with persistent calyx.
Floral Formula:
Monocotyledonae:
Family Liliaceae-Lily family:
Classification:
Class—Monocotyledoneae. Series—Coronarieae. Order—Liliales.
It is cosmopolitan family of 250 genera and 4000 species, about 200 of which occur in India.
Habit:
Usually perennial herbs growing by means of rhizomes (e.g., Aloe, Polygonatum), bulbs (e.g., Lilium, Allium) and corms (e.g., Colchicum). Some herbs are annual (e.g., Asphodelus). Shrubs occur in Aloe, Agave, Yucca (Dagger Plant, Adam’s Needle), Dracaena (Dragon Plant), and Ruscus (Butcher’s Broom).
They mostly grow in arid areas and are hence xerophytic (e.g., Aloe, Yucca). Xanthorrhoea of Australia is tree-like. Aerial stems of up to 10 metres height are found in Dracaena, Agave and Aloe dichotoma. Climbers are seen in Similax, Gloriosa and species of Asparagus.
Root:
Adventitious, fibrous or tuberous (e.g., Asparagus).
Stem:
Aerial or underground (rhizome, bulb, corm), aerial stem erect, prostrate or climbing, herbaceous or woody, cladodes occur in Ruscus and Asparagus.
Leaves:
Radical, cauline and ramal, cauline and ramal show various types of phyllotaxy (alternate, opposite or whorled), exstipulate, stipulate in Smilax where the stipules are prolonged into tendrils, sessile or petiolate with sheathing leaf bases, venation parallel but reticulate in Smilax, leaves may be scaly, leathery, fleshy or modified into spines (e.g., Asparagus), leaf apex is tendrillar in Gloriosa.
The leaves of Phormium tenax (New Zealand Hemp) are 3 metres long and 10 cm broad.
Inflorescence:
Recemose, sometimes solitary (e.g., Tulipa, Gloriosa) or umbellate condensed cymes (e.g., Onion). In several cases the inflorescence possesses a leafless peduncle called scape.
Flower:
Bracteate or ebracteate, pedicellate, regular, actinomorphic, zygomorphic in a few cases (e.g., Gilliesia), complete or incomplete, perfect, unisexual in Smilax and Ruscus, hypogynous, generally pentacyclic, trimerous (rarely bimerous or tetramerous). Accessory floral orogans undifferentiated and collectively called perianth.
Perianth:
6, in two whorls of 3 each, free or fused, sepaloid or petaloid, scarious or membranous, aestivation valvate or imbricate, distinguished into calyx and corolla in Trillium, inferior.
Androecium:
6 (3 in Ruscus, 9-12 in Tofieldia), free (polyandrous) or monadelphous (e.g., Ruscus), arranged in two whorls, antiphyllous (antitepalous), may be epiphyllous (or epitepalous), anthers fixed variously (basifixed, dorsifixed, versatile), dehiscence longitudinal or by pores, inferior.
Gynaecium:
Tricarpellary, syncarpous, ovary superior, trilocular with 2-many ovules in each loculus, placentation axile, rarely parietal, styles united or separate, stigma free or fused, trilobed.
Fruit:
A capsule (e.g., Asphodelus, Gloriosa) or berry (e.g., Asparagus).
Seed:
Endospermic and monocotyledonous.
Diagnostic Characters:
(1) Plants usually perennial herbs or shrubs.
(2) Leaves simple, exstipulate with sheathing bases and parallel venation (exception found in Smilax).
(3) Trimerous, hypogynous and pentacyclic flowers.
(4) Calyx and corolla undifferentiated and called perianth. Perianth 6, in two alternate whorls.
(5) Androecium 6 in two whorls, antitepalous, often epitepalous.
(6) Gynaecium tricarpellary, syncarpous, ovary trilocular with axile placentation.
(7) Fruit capsule or berry.
Economic Importance:
1. Vegetables:
The young shoots and root tubers of Asparagus species are cooked. The bulbs of Onion (Allium сера) and Garlic (Allium sativum) are also edible. They are added to vegetables as flavouring agents.
2. Perfume:
Perfume yielding plants are Convallaria majalis (Lily of the Valley) and Hyacinthus orientalis.
3. Fibres:
They are obtained from the leaves of Phormium tenax (New Zealand Hemp), Agave (e.g., A. Americana, Century Plant), Yucca (e.g., Y. gloriosa, Dagger Plant), Sansevieria (e.g., S. roxburghiana, Bowstring Hemp).
4. Resin:
It is obtained from Xanthorrhoea and Dracaena species. The resin is mostly used in varnishes and sealing waxes.
5. Poison:
Bulbs of Urginea maritima and Scilla yield raticide. Swollen roots of Gloriosa superba are highly poisonous.
6. Medicines:
Aloe barbadensis gives a drug aloin which is laxative and is sometimes applied on boils and burns. The juice of Garlic (Allium sativum) is useful against bronchitis, flatulence, blood pressure and gout. The poisonous roots of Gloriosa superba (Glory Lily, Vern. Kalihari) have properties to cure leprosy, piles, gonorrhoea, scorpion bites, etc. Leaf juice can kill lice.
The dried corms of Colchicum autumnale yield colchicine which is used in cytology for doubling the number of chromosomes (polyploidy). Corms of Colchicum luteum are used in the treatment of rheumatism, gout, liver and spleen diseases. Roots of Smilax zeylanica (Vern. Ram Datun) yield sarsaparilla like drug for purifying blood (curing boils), piles, leprosy, gonorrhea, etc.
7. Ornamentals:
Asparagus, Hyacinthus, Gloriosa, Lily, Tulip and Smilax are grown in the gardens.
Type 1. Allium сера (Onion, vern. Piaz, Fig. 5.140.
Included under Amaryllidaceae.
Inflorescence:
In apparent umbel formed by the aggregation of many monochasial cymes with many scaly outgrowths, surrounded by one to three large membranous bracts and borne on a leafless scape. Flowers are sometimes replaced by bulbils.
Flower:
Ebracteate, pedicellate, regular, actinornorphic, incomplete, perfect (hermaphrodite), trimerous, hypogynous, white. The outer sterile floral whorls undifferentiated and are called perianth.
Perianth.
6. in two whorls of 3 each, the tepals of one whorl alternating with those of the other whorl, gamophyllous, campanulate, odd tepal of the outer whorl anterior, petaloid, white with generally green midrib, inferior.
Androecium.
6, in two whorls, opposite the tepals, polyandrous, epiphyllous (adnate with the tepals only at the base), exserted, filaments slightly dilated at the base, anthers long and dorsifixed, dehiscence longitudinal, inferior.
Gynoecium.
Tricarpellary, syncarpous, superior, ovary trilocular with two ovules in each loculus, placentation axile, style short, stigma minute.
Fruit.
A loculicidal capsule with endospermic seeds.
