The present paper, which is offered as a portion of a thesis for the degree of Master of Science at the Massachusetts Agricultural College, is one of a series of studies being conducted at this institution on the anatomy of the Carolina locust for the purpose of furnishing a description of the morphology of a common and widely distributed insect which is both primitive in its organization and of sufficient size to be readily dissected. In the preparation of this paper I have received much encouragement and assistance from Dr. H. T. Fernald, Dr. G. C. Crampton, and Dr. V. S. Regan, and I would take this opportunity of expressing my appreciation of their kindly interest and advice*