VESPERTILIONID^— NYCTALUS 



For the following table of measurements I am indebted to Charbonnier, 

 They were printed on page 65 of Lloyd Morgan's Animal Life and 

 Intelligence (London), 1 890-1 891 : — 



Proportionate lengths : — Foot (without claws), about -45 of lower 

 leg; fifth metacarpal, about -82 of third; lower leg, about -41 of fore- 

 arm, and about -29 of head and body. 



Skull : — Greatest length, 15 ; basal length in middle line, 1 1-25 to 12 ; 

 palatal length in middle line, 5-5 to 6; from posterior border of vi^ 

 to anterior border of canine, 6-5 to 6 ; ditto in lower jaw, 6 to 6-5 ; 

 greatest breadth at zygoma, 10 to 10-5; posterior breadth, 9; breadth 

 between orbits, 8 ; breadth at constriction, 5 (nearly). 



Weight: — 14 to 20 grammes (Moffat, IrisJi Naturalist, 1900, 235). 



Distinguishing characters : — Lack of familiarity with this bat has 

 led most naturalists to regard its identification as difficult, and even 

 to confuse it with N. noctula. The two, however, when closely compared 

 are remarkably different, and, apart from the distinctions based upon 

 dimensions, colour, and odour, the relative proportions of the wing, 

 lower leg, and foot, are infallibly diagnostic (Plate V., p. 64). The only 

 other British species which bears any resemblance to Leisler's Bat is the 

 Pipistrelle, but here again there is no need to search farther than the 

 length of the forearm for points of distinction. 



The bat on which Bell, following Leisler, bestowed the 

 not very satisfactory name of Hairy-armed, was first dis- 

 covered by the latter naturalist in Germany, and described by 

 Kuhl in 1819 ; it has ever since remained one of the least 

 known of English bats. It made its first appearance as a 



