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XV. Some Observations on the Common Bat of Fennant : with 

 an Attempt to prove its Identity with the Pipistrelle of French 

 Authors. Bi/ the Rev. Leojiard Jenyns, M.A. F.L.S. Com- 

 municated by the Zoological Club of the Linnean Society. 



Read February 3, 1829- 



It has been usual with every systematic writer upon British 

 zoology from the time of Pennant to the present day, to refer 

 the Common Bat of this country to the Vespertilio murinus of 

 Linnaeus. Upon the correctness or incorrectness of this con- 

 clusion it were not, perhaps, at this period very easy to speak 

 with certainty ; since many of the descriptions of that author, 

 from the paucity of species then known, are drawn up in such 

 vague and general terms as to admit of application to several 

 others besides the one originally alluded to. It is, however, 

 somewhat remarkable that no one should ever have observed 

 the striking disagreement between our English Bat and that to 

 which the continental authors have continued to give the Lin- 

 nean name, and the consequent impropriety of referring both 

 these to the same species and making them synonymous. This 

 difference resides not merely in the colour and general appear- 

 ance of these two Bats, comparatively viewed, — in the shape of 

 the auricle and its operculum, and in some of their relative 

 dimensions, — but most palpably in their absolute size. In the 

 detailed descriptions of the Vespertilio murinus given by GeofFroy 

 and Desmarest, we find the average measurements of this species 



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