Recent Progress in Hormone Research, Volume 24 covers the proceedings of 25th meeting of the Laurentian Hormone Conference, held in Mont Tremblant, Quebec on August 2-September 1, 1967. This book is organized into six parts encompassing 13 chapters, and begins with reviews on the mechanism of action of various hormones. The next parts deal with the activation by hormones of adenyl cyclase in various tissues and the intermediation of 3′, 5′-cyclic adenosine monophosphate. These topics are followed by discussions on the functions of the gonadotropins and the control of the ovary and testis by the pituitary. Other parts consider the progress in defining the nature and action of the hormone thyrocalcitonin. The remaining parts examine the insect juvenile hormone of the complex vertebrate endocrinology. This book is directed primarily toward endocrinologists and biologists.