Pharmacognosy of Chlorophytum tuberosum Family Liliaceae This is a genus of two hundred species and twelve are native to India. These are rhizomatous herbs and roots fascicled, often thick fleshy and tuber like. It is a rhizomatous herb. Leaves are suberect lanceolate and many nerved. Inflorescence is an erect, dense-flowered racemes. Flowers are star like, white upto 2 cm across, sepals are acute, anthers are longer than filaments are green or yellow in colour, bracts are long. Seeds are black in colour with angular edges.

Pharmacognosy of Calotropis procera Botanical Origin : Calotropis procera ( Ait.) R.Br. Family : Asclepiadaceae Arka, an important drug of Ayurveda is known in this country from the earliest time. It is mentioned by the earliest Hindu writers and the ancient name of the plant which occurs in the vedic literature was Arka alluding to the form of leaves, which was used in the sacrifical rites. There are two common species of Calotropis, viz. C. gigantea ( Linn.) R.Br. and C. procera (Ait.) R.Br. described by the Sanskrit writers. Both the species are used as substitutes for one another and are said to have similar effects. One species is more commonly used in some parts of the country, while the other parts use the other species depending on the availability of their distribution.

Pharmacognostical characterization of some selected medicinal plants. History of Pharmacognosy:

Collection of important medicinal plants from different regions of Rajasthan. Introduction– Rajasthan has a large population of about 5, 64, 73, 122 crore. Around 80 percent live in villages which utilizes local medicine. The people of Rajasthan can be broadly divided into ; those living into extreme wheather condition as in Western Rajasthan and others in milder climate. Rajasthan has rich biodiversity consisting of a large number of plants, some of which are used for their medicinal value. Although flora of Rajasthan has been compiled by Bhandari (1978) and Sharma (1976) but detailed information about their medicinal properties are lacking.

The Role of ethnobotany in relation to medicinal plants in India. Ethnobotany is usually defined as anthropological approach to botany. There are several methods of ethnobotanical research and those relevant to medicinal plants are archaeological search in literature, herbaria and the field studies. “Man, ever desirous of knowledge, has already explored many things, but more and greater still remains concealed; perhaps reserved for far distant generations, who shall prosecute the examination of their creator’s work in remote countries and make many discoveries for the pleasure and convenience of life…” The above quotation of Linneaus is the most appropriate to this chapter which deals with the relationship between medicinal plants and the total filed of ethnobotany.

Family Fabaceae dominates the plant world and consists of a large number of plants which are having Ayurvedic medicinal importance. This family Fabaceae consists of 600 genera with 12000 species and are arranged in three well defined sub families and they are Papilionaceae, Caesalpiniaceae and Mimosaceae. The sub family Papilionaceae consists of 400 genera with 7000 species. The sub family Caesalpiniaceae consists of 56 genera with 650 species. The sub family Mimosaceae consists of 23 genera with 550 species.