It is suggested by the Committee that members of the American Anthropological Association having occasion to describe clay vessels, may classify them: first, as to material, as consisting of clay, sand, shell, and their combinations, and as possessing certain general ground-color; second, as to manufacture, as sun-dried or fired, as coiled or modeled—with the variations and steps of each process; third, as to form; fourth, as to decoration, as plain, stamped, incised, or painted. With regard to form, the Committee begs to offer the following definitions and suggestions in classifications. (NOTE. In all cases measurements are considered as referring to an upward direction.) A simple vessel must consist of a body, and may have a rim, neck, foot, handle, or any combination. 1. Body: A formation capable of holding within itself a liquid or a solid substance. 2. Rim: (A) A part of the vessel forming the termination of the body. (B) A part of the vessel recognizable by a change in the thickness of the material in the terminal sections. 3. Neck. A part of the vessel recognizable by a more or less sudden decrease in the rate of increase or decrease of the diameter. 4. Foot. An attachment to the vessel which serves as support to the body when upright. 5. Handle: A part of the vessel consisting of some outside attachment, not serving as support. Body: It is suggested that in comparing the forms or cross-sections of vessels particular attention be paid to the proportion of the diameter to the height, to the rate of change of this proportion, to the place of change of direction in this proportion, and to refer to the following definitions of the two dimensions: Height: the distance from the base to a horizontal plane passing through the most distant part of the rim. Diameter: the distance from any one point on the sides to any opposite point on the sides, measured on a plane at right angles to the height. Base: the point of contact or a plane of contact of the body with a horizontal surface. Types. Body: These are so varied, depending on relative height and diameter of the cross-section, that an analysis is too cumbersome to be of service to general reference. Neck: 1. Expanding. 2. Cylindrical. 3. Contracting. 4. Combinations. Lip: A part of the neck or body recognizable by a suddenly increasing diameter of neck or body, that continues increasing to the rim. [Illustration: FIG. 25. (S. about 1–2.) Cores and flake knives from the ancient quarries, Flint Ridge, Licking County, Ohio. Material: light pink, white and brown chalcedony. Phillips Academy collection. ] Foot: 1. Continuous. (A) Expanding. (B) Cylindrical. (C) Contracting. (D) Combinations. Feet: 2. Not continuous. Differentiated by (A) Number. (B) Angle with the horizontal. (a) Expanding upward. (b) Perpendicular.