This publication is based on the research work carried out by the authors under the CSIR Project. India has a rich biodiversity of flora and fauna having biocidal and medicinal properties. The flora at Santhal Parganas (Jharkhand) is very rich and varied with biocidal (Piscidal, Insecticidal, Pesticidal) and medicinal properties. India has a rich biodiversity of flora and fauna having biocidal and medicinal properties. The flora at Santhal Parganas (Jharkhand) is very rich and varied with biocidal (Piscidal, Insecticidal, Pesticidal) and medicinal properties. The Knowledge of the chemical constituents of these Biocidial Plants advanced rapidly in the last few decades. The destruction of household pests and prevention of vectors of diseases like AIDS, Cancer, Diabities, Malaria, Filaria etc., is very important and common problems and a very good deal of attention has been paid in recent years. The present research work is an endeavour to elucidate the Biocidal Plants resources of Santhal Parganas, which have been divided under three parts and eleven chapters in this book in very simple and lucid language. The first and second parts of this book cover Survey, Phytochemical Studies and Ecological Studies of selected Biocidal Plants located in the forest areas of Santhal Parganas, Jharkhand which include four districts Viz. Dumka, Sahibganj, Godda and Deoghar. The third part of this book covers Toxicological aspects of Biocidal Plants which include a comprehensive and indepth investigation of the toxic effect of alkaloid extract of some selected Biocidal Plant like Datura metel, L., Strychnos nuxvomica, L. and Argemone mexicana.L., on the fresh water major carp and air breathing fishes, Scanning Electron Microsocpy (SEM) Study of alkaloid exposed fish gills, respiration physiology, haematological aspects, mucous glands and chromatophores of fishes. The research findings elaborated in this book would certainly open new avenues of research and development in the areas of Biocidal as well as medicinal plants research for the benefit of mankind and society as a whole. Contents PART -I Eco-Toxicology of certain Biocidal Plants Survey of Biocidal Plants of Santhal Parganas Phytochemical Studies of Biocidal Plants of Santhal Parganas-I Phytochemical Studies of Biocidal Plants of Santhal Parganas -II -- Extraction, Quantification, Separation and Identification of Alkaloids PART - II Ecological studies of biocidal Plants of santhal Parganas PART- III Toxicology of Biocidal Plants- I -- Toxicity of Alkaloid Extract on Fishes Toxicology of Biocidal Plants-II - Effect of Alkaloid Extracts on Bimodal Oxygen Uptake on Air-breathing Fishes Toxicology of Biocidal Plants- III -- Effect of Alkaloid Extract on Haematological Parameters of Air-breathing Fishes Toxicology of Biocidal Plants- IV - Effects of Alkaloid Extract on Fish Gill : [Scanning Electron Microscopy (SEM) of Indian Study of Gills Minor Carp Labeo Bata (HAM)] Toxicology of Biocidal Plants- V- effect of Alkaloid Extract on Chromatophores and Mucous Glands of Labeo bata General Discussion and Conclusions