Till'] I.ITTLK JiliOWN OR CAVE RAT. 



621 



MYOTIS LUCIFUGUS (Le Conte). 

 LITTLE BROWN BAT ; CAVE BAT. 



Myalls lucij'ugus Le Conte, McMurtrie's Cuvier, Animal King- 

 dom, Appendix, p. 431, 1831. 



Vespertilio gryphus Evermann and Butler, Proc. Ind. Acad. Sci. 

 for 1893, p. 134, 1894. 



Vespertilio suhulatus Blatchley, 21st Ann. Rept. Ind. State 

 Geol., p. 180, 1896. 



Myotis lucifugus Miller, N. Am. Fauna, No. 13, p. 59, 1897. 



Diagnostic characters. — A medium sized bat (expanse 10 in.), 

 varying in color from glossy wood brown to dull blackish; ears 

 when laid forward, barely reaching the nostrils; tragus short, 

 broad at the base, and blunt (fig. 28, a) ; the most common bat in 

 southern Indiana. 



Description. — It is difficult to formulate a description which will 

 enable anyone not familiar with bats to distinguish this species 

 from the next with certainty. The hairs of the back are always 

 sooty blackish at the base and this is usually concealed by the tips 

 of gloosy wood- or chestnut-brown. Occasionally the tips are also 

 dull sooty or clove brown. The belly is always paler and usually 

 has a yellowish tinge. In suhulatus the back is apt to have a grayer 

 tinge while the hairs of the under side are usually, but not always, 

 pure white or silvery without the yellow tinge. Membranes and 

 ears dull blackish. 



Ears rather short and blunt, broad at the base and suddenly be- 

 coming narrower one-third of the distance from the tip; tragus 

 short, wide at the base, blunt and bent forward; membranes thick 

 and naked except a narrow row of fur nearest the body and a few 

 short hairs scattered over the surfaces; interfemoral and wing 

 membranes arising from the base of the toes; calcar slender, with 

 a narrow edge of membrane posterior to it. 



Measurements. — Average of ten individuals from Mitchell: 

 Total length, 89.4 mm. (3 9/16 in.) ; tail, 38.7 mm. (li/g in.) ; hind 

 foot, 9.9 mm. (% in.) ; forearm, 37.4 mm. (1% in.) ; tibia, 16.6 

 mm. (% in.) ; ear, 11 mm. (7/16 in.). 



Shull and teeth. — The skull, for a myotis, is froad and has a 

 gradually sloping forehead. The face line begins to rise almost 

 from the tip of the muzzle, while in suhulatus the braincase rises 

 abruptly in the region of the eyes; braincase broader and higher 

 in lucifugus; muzzle also broader and the skull, as a whole, appears 

 to be much stronger and heavier; tooth row shorter in lucifugus; 



