Geological Age of the Cheiroptera. 27 



ancients have not left us any monument which expressly repre- 

 sents any living animal of this family, unless we put down to this 

 account the figure which they frequently give of the Harpy, 

 which, in reality to a considerable extent, resembles it. But if 

 bats have thus left no traces of their existence upon the surface 

 of the globe, except in the writings of man, it is very different 

 in the successive layers of the crust of the earth, or in what is 

 usually denominated the fossil state. Without particularly 

 enumerating the different discoveries which have been made on 

 the point, during the century and a half to which the attention 

 of naturalists has been directed to this subject, we shall only 

 notice that he sums up, nearly in the following terms, our pre- 

 sent knowledge of fossil remains of the Cheiroptera. 1^^, Ani- 

 mals of this family existed before the formation of the middle 

 tertiary deposits of the northern or European countries, 

 since undoubted remains are found in the gypseous formation 

 in the neighbourhood of Paris. 2c?Z2/, These bats were pro- 

 bably contemporaneous with the Anoplotherium and the Pa- 

 loeotherium, as their bones are found in a similar geological 

 position. Sdlt/, They have continued uninterruptedly to exist 

 from that time to the present day, and that throughout the 

 whole of Europe, because their remains are found in the dilu- 

 vium of caverns and in osseous breccias. 4^/i/z/, That these 

 very ancient bats do not differ much, if indeed they differ 

 at all, from the species which are now living in these same 

 countries. Hence it may be deduced as a legitimate result, that 

 the conditions of existence which are essential to them now 

 were the same at that epoch, more or less distant from the pre- 

 sent time, and, therefore, that there has been no considerable 

 change in the totality of the circumstances, or at least these 

 changes must have been in the last degree insignificant, and in 

 limits of variation such, that the maxima and minima oscillate, 

 as they now do, without any appreciable influence upon orga- 

 nized beings. 



M. de Blainville concludes by giving us a synopsis of the 

 arrangement of the genera, including the principal species ; but 

 what we have said above may suffice for the comprehensioQ of 

 his classification. 



