being 210 feet high and 1600 by 600 yards. The eastern island is slipper shaped, 200 feet high and 1600 by 600 yards. The north face of both islands and to a slightly less degree the south face also, is a sheer limestone cliff, with numerous caves, both at sea level and higher up the face. Some of those caverns are of considerable size. Anchored off the middle of the W. island at 3:30 and ashore by 4 P.M., landing on a sand beach in a small bay, at the east end of the western island. A sunken reef with a "mushroom" rock on it connects the two islands and is awash at low tide. From the beach a good trail leads first to a small grove of coconut palms and then into the woods. The entire central portion of the island, quite in contrast to the rough forbidding sides, is a flat, nearly level, smooth plateau, in places higher than the enclosing walls, and covered with a moderately open stand of the usual lowland trees. They are for the most part of considerable size, some of the strangling banyans attaining a height of 50 to 60 feet and a diameter between the external "props" of 25 or more feet. In places there is quite a tangle of vines, but open "avenues" extend through the thickets making trails unnecessary. Here and there there is a deep sink or pot hole (like those on Ewa Coral Plane), with sheer walls, 20 to 30 feet deep and of various sizes, some with caverns extending back from the sides, and with large trees growing on the level bottoms. Walked west a little more than half the length of the island near the north side; then across the island to the top of the south face, which is less percipitous here; and diagonally back to the landing beach. Saw a brown rat. Landshells not plentiful, perhaps too dry. A very few on rock faces and one here and there on leaves. Too late in the day for good insect collecting. Caught a few small moths and some small spiders, flies, etc. Mt. Beck found a large brown X corei'd