1909.1 THE CAYUGA LAKE BASIN, N. Y. 459 



collected outside the basin indicate that its occurrence here is limited 

 to the fall. 



390. Lasiurus borealis (Miiller). Red bat. 



One of the most abundant bats of the region. In the spring they 

 are not much in evidence until the middle of May and disappear the 

 last of October. 



391. Lasionycteris noctivagans (Le Conte). Silvery-haired bat. 

 Common, especially in the gorges. It appears the first of May, 



the migration reaching its height by the middle of the month. 



392. Pipistrellus subflavus (F. Cuvier). Pipistrelle. 



Common, especially in the gorges. It appears in the spring the 

 first of May along with the silvery-haired bat and is the last of all 

 our bats to disappear in the fall. Specimens have been taken as late 

 as November i. 



393. Vespertilio fuscus Beauvois. Big brown bat. 



Common. It is the first bat to appear in the spring. It may be 

 looked for the first of April a month before any of the others are 

 seen. 



394. My Otis subulatus (Say). Say's bat. 



One specimen taken at Ithaca, July 2, 1904, by A. G. Hammar. 



395. Myotis lucifugus (Le Conte). Little brown bat. 



This is the most common bat of the region. They appear in the 

 spring the last of April. 



