MICROCHIROPTERA 



135 



Characters. — Anterior limb very highly modified, the second 

 finger scarcely if at all independent of third, its ungual phalanx 

 never present, the humerus with trochiter and trochin large, the 

 former usually articulating with scapula ; mandible with angular 

 process well developed, long and narrow ; teeth usually not 

 modified for frugivorism (never in European species), the cheek- 

 teeth of upper and lower jaws very different from each other 

 (except when excessively reduced, as in the South American 

 Dfismodontidse) ; margin of ear not forming a ring ; tragus usually 

 present. Mammae in all European genera, j^ 1-1 = 2. 



JRemarks. — The sub-order Microcluroptera is essentially cos- 

 mopolitan in distribution. Though more highly modified than 

 the Megacliiroiitera in wing structure, the members of this group 

 for the most part retain the primitive tuberculo-sectorial type of 

 molar tooth, though certain South American frugivorous forms 

 show the stages through which the Megachiropterine molars 

 have probably passed. At present 17 families and nearly 150 

 genera are recognized ; the species are too imperfectly known to 

 permit any approximate estimate of their number. Three 

 families and ten genera are found in Europe. 



KEY TO THE EUROPEAN FAMILIES AND SUB-FAMILIES 

 OF MICROCHIROPTERA. 



Tragus absent ; muzzle with leaf-like outgrowths ; 

 premaxillaries represented by palatal branch 

 only, not fused with surrounding parts (often 



lost in prepared specimens) Rliinolophidai, p. 136. 



Tragus present ; muzzle without leaf -like out- 

 growths ; premaxillaries represented princi- 

 pally (entirely in European genera) by nasal 

 branch, very early and completely fused with 

 surrounding parts. 

 Fibula robust, its diameter about half that of 

 tibia ; tail projecting conspicuously beyond 

 hinder edge of narrow interfemoral mem- 

 brane Molossidx, p. 276. 



Fibula very slender, its diameter much less than 

 half that of tibia ; tail scarcely or not pro- 

 jecting beyond hinder edge of broad inter- 

 femoral membrane Vcspcrtilionidee, p. 165. 



Presternum with median lobe nruch smaller 

 than body of bone ; coracoid curved out- 

 ward ; second phalanx of third finger not 



specially elongated Vespertilion'um, p. 165. 



Presternum with median lobe lai-ger than 

 body of bone ; coracoid straight, directed 

 inward ; second phalanx of third finger 

 nearly three times as long as first Minioptennie, p. 26S. 



