INTRODUCTION, XVll 



but probably mucli more effective than the vibrissce of other species, 

 supplementing in the animals in which they are developed the feeble 

 aid given by the small eyes in distinguishing objects approached in 

 rapid flight during the hours of darkness*. 



In all species of Bats with nasal appendages there may be found 

 more or less weU-developed glandular prominences on the sides of 

 the face between the eyes and the extremity of the muzzle. In some 

 genera they are small and concealed by the fur (as in Vespertilio and 

 Kerivoula), in others large and nearly naked, forming prominent 

 rounded elevations (as in Vesperugo, Plecotus, and Synotus), but in 

 all long and straight fine hairs arise from them, which are evidently 

 analogous and homologous to the vibrissce of the Felidce and other 

 Mammals. In some specimens of Plecotus auritus these glands are 

 found unusually large, forming rounded prominences, raised sUghtly 

 above the margins of the naked crescentic depressions behind the 

 nostrils (Plate XI. fig. 9). These prominences in Plecotus (Corino- 

 rhinus) macrotis are greatly developed vertically, forming high conical 

 processes which, bending inwards over the nasal grooves, meet in 

 the centre above and behind the nostrils, concealing the grooves 

 beneath (Plate XI. fig. 8). In front the nasal apertures in this 

 species are margined by a narrow, flat, cutaneous ring. In Nycto- 

 philus (which is closely related to Plecotus and Synotus) the same 

 prominent glands of the muzzle have become united in the centre 

 above (evidence of their distinct origin being stiU afforded by the 

 presence of a longitudinal furrow above), while the cutaneous mar- 

 ginal rings surrounding the nasal apertures in P. macrotis are here 

 expanded and united together above and behind the nostrils, form- 

 ing a small nose-leaf, which is supported behind by the united 

 glandular prominences (Plate XI. fig. 7). In the much more highly 

 differentiated nasal processes of Megaderma, especially of M. spasma, 

 the homologies of these parts with the glandular prominences and 

 rudimentary nose-leaf of NyctopMlus may be easily recognised. 



This, then, is evidently the mode in which the very complicated 

 nasal appendages of RhinolopJms and other genera have originated, 

 whence it follows that they are partly composed of the marginal in- 



* Bats without nasal appendages are more properly crepuscular and matutinal 

 than nocturnal in their habits (see description of habits of Molossus obscurus, 

 p. 412). The nose-leafed species fly much later, and this is probably one of the 

 reasons why they are less commonly shot on the wing. Mr. Tomes has noted 

 the much finer sense of touch possessed by a leaf-nosed Bat, as shown when 

 flying in company with a simple-nosed Bat in a confined space. 



