Many early works of botanical microscopy and pharmacognosy, as well as modern pharmacopoeias, give emphasis to the microscopic analysis of powdered plant drugs. As noted elsewhere in this text, many plant parts share the same characteristics, so viewing fragments in powders may not give a definitive determination for identification. For purposes of identification of plants to species with the greatest level of confidence possible, emphasis in this work is given to the arrangement of tissues within a relatively whole piece of material, in contrast to the presence of tissue fragments in powders.