8 INTRODUCTION 



six Pipistrelles in the Dublin Museum, the ears have shrunk to 

 little more than half their natural size, thus completely changing 

 their appearance.^ Some such circumstance probably accounts 

 for an error in Dobson's description of the ears of the 

 Barbastelle. 



Even more important is the wing (Fig. 3), which consists of 

 a thin cutaneous membrane. This, in its complete development. 



Fig. 3. — Wing of a Bat (diagrammatic). 



Membranes .—am, antebrachial ; Im, lateral ; im, interfemoral ; dp, dactylopatagium ; 

 pel, post-calcarial lobe. Skeleton : — A, humerus ; r, radius ; », ulnar ; w, wrist ; di, 2, 3, 4, 5, 

 digits I, 2, 3, 4, 5 ; mi, 2, 3, 4, 5, metacarpals I, 2, 3, 4, 5 ; / femur; 16, tibia; Ji, fibula; 

 /, foot ; c, calcar or spur ; /, tail. 



arises at the neck at each side, and, including within its sub- 

 stance, somewhat like the ribs of an umbrella, the four limbs and 

 the tail, forms an uninterrupted parachute or patagium around 

 the body. The greater portion of this parachute is supported 

 by the forearms. In order to maintain it there is an immense 

 development of each hand or manus, in which the five fingers or 

 digits are always present. The basal joints of the digits are 

 not homologous with the finger-joints or phalanges of other 



' See Andersen, Ann. and Mag. Nat. Hist., Nov. 1906, y7'2.-2,T^. 



