ENDOCRINE ASPECTS OF CORPUSCLES OF STANNIUS IN SOME INDIAN FISHES

Fishes are aquatic vertebrates that are members of the largest and most diverse vertebrate taxon (30000 species) that dates back over 500 million years. They have evolved into three major lineages: Agnatha (hagfish and lampreys) Chondrichthyes (sharks skates and rays; usually referred to as elasmobranchs) and Actinopterygii (bony fishes with teleosts being the most prevalent). Fish have great significance in the life of mankind being an important natural source of protein and providing certain other useful products as well as economic sustenance to many nations.