MAMMALS OF MARYLAND 



11 



2a. Coloration reddish-orange Lasiurus borealis (red bat) 



b. Coloration brownish to black, frosted with white 3 



3a. Total length greater than 125 mm.; interfemoral membrane wholly 

 furred; coloration brownish, heavily frosted with white; individual 



hairs banded Lasiurus cinereus (hoary bat) 



b. Total length less than 120mm.; interfemoral membrane only partially 

 furred; coloration blackish, lightly frosted with white; individual hairs 



not banded Lasionycteris noctivagans (silver-haired bat) 



4a. Ears reaching considerably beyond end of nose when laid forward 5 



b. Ears not reaching noticeably beyond end of nose when laid forward 6 



5a. Ears greatly enlarged, over 35 mm. from crown in length 



Plecotus townsendii (big-eared bat) 



b. Ears not noticeably enlarged Myotis keenii (Keen myotis) 



6a. Over 100 mm. in total length Eptesicus fuscus (big brown bat) 



6. Under 100 mm. in total length 7 



7a. Under 85 mm. in total length; distinct black facial mask 



Myotis subulatus (small-footed myotis) 



b. Over 85 mm. in total length ; no black facial mask 8 



8a. Pale golden brown in coloration ; nose, ears, and wings reddish-brown 



Pipistrellus subflavus (eastern pipistrelle) 



b. Coloration dark brown; ears, nose, and wings nearly black 9 



9a. Fur long, thick, and shiny Myotis lucifugus (little brown bat) 



b. Fur short, dull and sparse 10 



10a. Coloration dark brown; ears thick and leathery 



Nycticeius humeralis (evening bat) 

 b. Coloration pinkish brown; ears not thick and leathery 



Myotis sodalis (Indiana myotis) 



Key to the Order Lagomorpha in Maryland 



la. Length of hind foot greater than 115 mm (as much as 150 mm. in some 

 specimens) ; coloration white in winter 



Lepus americanus (showshoe rabbit) 

 b. Length of hind foot less than 115 mm.; coloration brownish in all 



seasons 2 



2a. Black on forward edge of ear sharply defined from brown of rest of 

 ear; distinct black patch betweep ears 



Sylvilagus transitionalis (New England cottontail) 

 b. Black on forward edge of ear not sharply defined; no dark patch 



between ears Sylvilagus floridanus (eastern cottontail) 



Key to the Order Rodentia in Maryland 



la. Upper incisors with longitudinal grooves 2 



b. Upper incisors without longitudinal grooves 5 



2a. Tail very short, equal to about one-sixth of total length 



Synaptomys cooperi (southern bog lemming) 



b. Tail longer than one-sixth of total length 3 



3a. Tail less than one-half of total length 



Reithrodontomys humulis (harvest mouse) 

 6. Tail greater than one-half of total length 4 



