CHAP. XVII.] MAMMALIA. 185 



Molossi to the rank of a sub-family. In our first volume we 

 have classed Ehinopoma with the Ehinolophidae, and Tapliozous 

 with the Vespertilionidse ; but according to Mr. Dobson both 

 these genera belong to the present family. 



Remarks on the Distribution of the Order Chiroptera. 



Although the bats, from their great powers of flight, are not 

 amenable to the limitations which determine the distribution of 

 other terrestrial mammals, yet certain great facts of distribution 

 come out in a very striking manner. The speciality of the Neo- 

 tropical region is well shown, not only by its exclusive possession 

 of one large family (Phyllostomidae), but almost equally so by the 

 total absence of two others (Pteropidse and Ehinolophidae). The 

 Nearctic region is also unusually well marked, by the total ab- 

 sence of a family (Ehinolophidae) which is tolerably well repre- 

 sented in the Palsearctic. The Pteropidse well characterize the 

 tropical regions of the Old World and Australia ; while the Ves- 

 pertilionidse are more characteristic of the Palsearctic and Nearctic 

 regions, which together possess about 60 species of this family. 



The bats are a very difficult study, and it is quite uncertain how 

 many distinct species are really known. Schinz, in his Synopsis 

 Mammaliurn (1844) describes 330, while the list given by 

 Mr. Andrew Murray in his Geogra'phical Distribution of Mam- 

 malia (1866), contains 400 species. A small number of new 

 species have been since described, but others have been sunk as 

 synonyms, so that we can perhaps hardly obtain a nearer ap- 

 proximation to the truth than the last number. In Europe there 

 are 35 species, and only 17 in North America. 



Fossil Chiroptera. — The fossil remains of bats that have yet 

 been discovered, being chiefly allied to forms still existing in the 

 same countries, throw no light on the origin or affinities of this 

 remarkable and isolated order of Mammalia ; but as species very 

 similar to those now living were in existence so far back as 

 Miocene or even Eocene times, we may be sure the group is one 

 of immense antiquity, and that there has been ample time for 

 the amount of variation and extinction required to bring about 



