O. P. PEARSON Myotis yumanensis and/or lucifugus Aug 9. Bats in large numbers flew at late dusk between spruce and bog pond and over camp. Two shot proved to be this species and most looked similar. Aug 10 Started bat hunting at dusk in meadow east of camp but only bats seen were about 5 flying rapidly towards west, none circling. Then west to spruce by log pond where many were circling. Shot 2. Aug 11 Clear dark flight and also some shining pond at 9:00 and 9:45. Shot one of these by gooklight. Aug 13 Bat flight continues to follow novel pattern - appear about 7:30 between spruce + pond, then work out over the pond at about the time it becomes too dark to shoot. Aug 14 Evening cooler than most and murkier. Bat flight less dense and their feeding more scattered. Appeared later than usual - netted one on my first sweep, none on later sweeps. Aug 16 Evening cool + clear. Few feeding by spruce but some out over bog pond. Aug 17 Disappeared the morning about 5:20 flying in remarkably straight lines without swerving, towards the forest to the east.