such as are found at Sayil, and Labna and elsewhere (Pl. XXV, 1; p. 332). [Illustration: _PLATE XXV_ _Photo. Col. F. H. Ward_ 1 _Photo. Dr. A. P. Maudslay_ 2 MAYA 1. BUILDING AT SAYIL, YUCATAN 2. TEMPLE AT TIKAL, GUATEMALA] Mortar, obtained by burning the local limestone, besides being used in great quantities for the hearting of buildings, was also employed for flooring, and, as stucco, for making up defects in wall-surfaces and designs. Besides this it was extensively used for moulded decoration at certain sites, notably Palenque. Here the limestone is of a very hard variety, and difficult to work with such tools as the Maya possessed; as a result, the art of modelling in relief attained a great development, and some of the finest works of Central American art are those produced by the stucco-workers of Palenque. Where the relief is low, the stucco has been employed alone, but where bold effects were desired, as on the roof-combs, a regular skeleton of the design has first been prepared, of limestone blocks, over which the stucco has been applied and moulded to the requisite form. Colour formed an important aid to Maya ornament, and was frequently applied to stone carvings. It seems to us rather barbarous to cover fine stone reliefs with a coat of coloured stucco, but the Maya artist had no scruples on this score, and reliefs have been found at Palenque to which several layers of the above have been applied at different times. Many of the stelæ, especially at Piedras Negras, still show evident traces of colour, and it must be remembered that when the details were picked out in different tints the designs appeared far less complicated than in monochrome. But apart from the colouring of reliefs, fresco designs in a variety of hues were commonly applied to the interior walls of buildings, and their graceful and flowing lines prove that the Maya was no mean artist with the brush. This form of ornament has been observed at Menché, where a design of scrolls, leaves, flowers and figures of men and animals is painted on the walls of one of the chambers, in two reds, two blues, yellow and dark brown. At Chichen Itza the art of fresco was highly developed; not only were the columns, doorposts and interior reliefs painted in colours, but many chambers were elaborately ornamented with coloured designs. According to Miss Breton, who has made a careful study of these frescoes, two different hands may be traced in the method of execution. One artist employed outlines but sparingly, and carried out the greater part of his work in dry colour, sometimes superimposing one tint on another to obtain the desired effect. The other drew all his figures in outline and added the principal colour masses while the plaster was still damp, putting in the details subsequently in dry colour. The hues include two reds, two blues, four greens, yellow, white, black and purple. The practice of ornamenting wall-surfaces with painted designs