Initially published by the Linnean Society, this 1865 essay was Darwin's first foray into the study of climbing plants. He was inspired to produce this work by a paper on the tendrilled Cucurbitacean plant by American botanist Asa Gray, with whom he had a firm intellectual friendship. Darwin examines in detail those plants which climb using a twisting stem, such as the hop; leaf-climbers, such as the clematis; tendrilled plants such as the passion flower; and hook and root climbers such as ivy. The conclusions reached by his study are presented in terms of the adaptations of various species to their environments, a continuation of the theories that Darwin had propounded in his On the Origin of the Species six years earlier. His passion for the design of the plants and fascination with the diversity of their powers of movement are clear in this accessible example of the process of evolution.