A Preliminary Revision of the North American Species of Cactus, Anhalonium, and Lophophora

A scientific publication written in the late 19th century. This work focuses on the taxonomy and classification of various species of cacti native to North America, particularly examining the genera Cactus, Anhalonium, and Lophophora. The text aims to provide a systematic framework to better understand the complexities and variations in this group of plants, encouraging further exploration and collection of specimens. The opening of the work sets the stage for this detailed exploration of cacti. It begins with a transmittal letter from the U.S. Department of Agriculture and discusses the inception of the revision project, including fieldwork conducted to gather specimens and observations. John M. Coulter outlines the challenges associated with studying cacti due to the scarcity of flower or fruit specimens and describes the collaborative efforts undertaken with his assistants and other organizations to organize and classify the materials collected. The initial revisions presented provide insights into specific species, noting variations in structure and growth, which will guide future research and classifications in the field of botany.