Quast 1948 Macroctus californicus 3 May 20 San Antonio, [illegible], Baja California. entrance and in a place where the air could be felt to be circulating. Upon being frightened at our approach all but four of the specimens flew back to an inaccessible part of the mine. Four flew towards the entrance, three of which were captured by the group later. May 20 1 mile E of San Antonio, Baja California [illegible] About 80 of this species caught today in a mine at about this location. The mine is situated in a hill covered with Palo blanco tree and occurs where the general direction of the road changes from about East to South on the east side. The mine was composed of a horizontal tunnel at road level with several blind passages leading off it and a main vertical (45°) passage that led from the main horizontal shaft to an opening in the hill about 200 ft higher than the first one. Near the upper opening are three blind passages in which the late of this species and also 'Leptonycteris' were caught. Both types were found in the same passages but they were disturbed when we reached them. They were in the passage closest to the outside on the upper level when discovered (About 5:30 P.M.) and flew to the interior when disturbed by a shot by Dr. Benson. Both types were captured by chasing them