In the upper center of plate 10, _b_, may be distinguished a trench, 3 feet in width, which runs through the whole thickness of this layer. Its walls are composed of rough limestone blocks mortared together. The trench was completely filled in with small loose rubble similar to that found in layer _a_. The high, steep, solidly constructed mounds, the bases of many of which are connected with more or less circular earthworks, were probably lookouts or observation mounds. Most of these mounds terminate in a narrow flattened summit too small to have supported even the smallest temple, while many of them form the centers or nuclei of other groups of mounds. Few contain anything besides the stone, mortar, and earth of which they are constructed, though some of them contain superficial interments. That at Santa Rita is exceptional in that it includes stone-faced cysts. These mounds extend in a more or less regular chain along the coast of Quintana Roo and British Honduras, reaching from the top of Chetumal Bay nearly as far south as Northern River, and extending inland in a southwesterly direction along the courses of the Rio Hondo and Rio Nuevo, though many are situated at a considerable distance from either sea or rivers. MOUND NO. 5 Mound No. 5 (No. 27 on the plan, fig. 14), situated about 200 yards to the southeast of the fortification, was 3 feet in height, 30 feet in diameter, and nearly circular. It was built of blocks of limestone, rubble, limestone dust, and earth. Many of these blocks had evidently been taken from some building, as they were well squared. About the center of the mound, at the ground level, a small cyst was discovered, 3 feet long, 2 feet broad, and 1 foot high, built throughout of rough flags of limestone. Within it were two vases; one, shown in figure 21, _a_, is of rough unpainted pottery, 4-1/2 inches high, with a small ear-like projection on each side, each of which is ornamented with an ear plug. Vases with these ear-like projections and ear plugs are not uncommon in this area, and are probably highly conventionalized incense burners. The figure of the god outside (which, as will be shown later on, was represented after a time by the face only) has here had every feature and ornament of the face eliminated with the exception of the ears and ear plugs, which would always be unmistakable. [Illustration: PLATE 10 a. SECTION THROUGH EARTHWORK INCLOSING CIRCULAR SPACE. SANTA RITA b. SECTION OF WALL THROUGH SANTA RITA.] [Illustration: PLATE 11 EGG-SHAPED VASE FROM MOUND NO. 5]