AMERICAN BATS — ^HANDLEY 133 



vanishing point in some specimens) ; Pt much larger than P3 ; P4 double- 

 rooted, almost as long in anteroposterior diameter at the cingulum as 

 the tooth is high. 



Glandular masses on muzzle slightly enlarged (fig. 7) ; nostril with 

 slightly reduced cornu and with posterior elongation (fig. 8) ; auricle 

 with anterior basal lobe complete and projected noticeably beyond 

 anterior edge of auricle (fig. 9); accessory anterior basal lobe small 

 and not projected beyond edge of auricle; transverse ribs on auricle 

 extend without interruption to posterior border of auricle; tragus 

 relatively broad and long; second phalanx of third digit equal to or 

 shorter than first phalanx (fig. 6); forearm averages relatively short; 

 calcar not keeled; interfemoral membrane attached to base of last 

 caudal vertebra. 



Measurements: See tables 7, 13. 



Kemarks: According to EUerman and Morrison-Scott (1951, p. 

 181), the subgenus includes only one species, P. auritus. They list 11 

 geographic races (fig. 13). 



Literature on the natural history of Plecotus auritus is extensive. 

 The following data were gleaned from English sources, mostly from 

 Alcock and Moffat (1901), Barrett-Hamilton (1910-1911), Matthews 

 (1952), and Millais (1904). For reference to the excellent studies in 

 Germany, see Eisentraut (1937). 



Habitat: Plecotus auritus is distinctly arboreal, characteristically 

 hunting in the foliage of large trees. Ash trees seem to be particularly 

 favored, but oaks and other deciduous species also may be frequented. 

 However, it is not unusual to see P. auritus hawking around the upper 

 shoots of hedgerows and willows, and sometimes it descends to forage 

 among the lower shrubs and flowers in gardens. Rarely it hunts low 

 over meadows, and has been observed to alight on cow dung to devour 

 the insects attracted there. 



P. auritus commonly hangs up by day in the summertime in old 

 boathouses, cowsheds, church attics, and similar places; behind 

 window shutters and under eaves of old houses ; in tree holes ; and even 

 on trunks of trees, sheltered only by the roughness of the bark. This 

 species may utilize separate sites as daytime sleeping places and 

 night-time dining-halls or lounges. Barns and outbuildings are 

 favored for the latter, but tree-trunks are also used. Accumulations 

 of insect remains in such places betray the nightly visits of the bats. 



Winter roosts are principally in caves, where crevices as well as open 

 chambers may be utilized. Attics of old houses and occasionally 

 hollow trees are also used. 



Behavior: In some parts of its range, as in Britain, P. auritus may 

 be one of the commonest and most widely distributed bats, yet its 

 habits render it less conspicuous^than many of the others. It is 



