Although cacti such as the saguaro and organ pipe have come to define the Sonoran Desert for many people, they represent some 170 species of columnar cacti foun

This volume - the first of this series dealing with angiosperms - comprises the treatments of 73 families, representing three major blocks of the dicotyledons:

Seeds are a vital part of life on earth. They are fundamental for plant reproduction, and many seeds play an important role in the diet of man and domestic and