BECHSTEIN'S BAT 



175 



above, whitish beneath. The moderately distinct line of demarcation 

 passes along the line of junction between wing and body and thence 

 to the base of the ear. 



The skull, as compared with that of M. nattereri, is larger, but 

 narrower ; it carries more prominently developed cranial ridges and 

 much bigger bullae (Fig. 16, No. 2, p. 174). 



The teeth are similar to those of M. mystacinus, but the tip of the 

 middle upper premolar reaches far beyond the cingula of the neighbour- 

 ing teeth (Figs. 16, No. 2, and 17, p. 174). 



The geographical variation of this rare bat is almost an unknown 

 quantity, but Thomas has rightly separated central Spanish examples 

 from Hungarian as the sub-species favonicus on the ground of their 

 markedly smaller ears and bullae. I cannot distinguish the few British 

 specimens available from the type of favonicus, but await further 

 material before identifying the British Bechstein's Bat with that form. 

 Both are distinctly smaller than the Hungarian. 



Proportionate lengths: — Foot, without claws, about -53 of lower 

 leg; fifth metacarpal about equal to third; lower leg about -46 of 

 forearm. 



Skull :— Greatest length, 17; basal length in middle line, 12-25; 

 palatal length in middle line, 7-5 ; from posterior border of m^ to 

 anterior border of canine, 6- 5 ; same in lower jaw, 7-25 ; greatest breadth 

 at zygoma, 9 ; posterior breadth, 8 ; breadth between orbits, 7 ; breadth 

 at constriction, 4-5. 



Distinguishing characters : — The large ear of Bechstein's Bat marks 

 it off very distinctly from every other British species except the Long- 

 eared, in which the ears meet at their anterior margins. In other 



