Quest 1948 Journal 49 May 4 Mulege 25° ±, Baja California incline upward for about 200 feet through three constrictions and three broader cavities. The slope was about 20 or 30 degrees and at one place it is necessary to lie flat and pull yourself through the fine dust that had accumulated in the cave. The cave opening is hidden from the valley floor by a lip of fragmented rock. Within the cave there are many side passages of small size leading to small pockets. The whole cave is filled with very fine dust. The bats were roosting in a second widening of the cave about 150 feet from the opening and considerably higher than the rest of the cave. There were many bats in the cave of which I netted four (1♂ Mormoops megacephala and 3♀ Macrotus californicus). Dr. Benson caught 10 Mormoops (4♂, 6♀) and 20 Macrotus (7♂, 13♀). Dr. Benson also caught 4 (2♀ ad, 1♂, 1♀ juv) Leptonycteris (?). The three types of bats were the only ones noticed or caught. It has been decided that the locality of the cave is ¼ mi south of the mission at 100 feet. May 5 Bahia Concepcion 13 mi SE Mulege Baja California Minimum temperature here last night was 68°F, Maximum today was 92°F. Today is clear and warm, the light being intense on the weather.