CHAP. XII.] 



THE AZORES. 



245 



found in any of tlie otlier Atlantic islands, showing that they 

 have been introduced directly from Europe by causes which 

 have acted more powerfully here than farther south. Besides 

 these there are thirty-six species not found in Europe, of which 

 nineteen are natives of Madeira or the Canaries, three are 

 American, and fourteen are altogether peculiar to the Azores. 

 These latter are mostly allied to species found in Europe or in 

 the other Atlantic islands, while one is allied to an American 

 species, and two are so distinct as to constitute new genera. 

 The following list of these peculiar species will be interesting : — 



Carabidj*:. 



Ancliomenus aptinoides Allied to a species from the Cfinaries. 



Bemhldium hesperiis Allied to the European B. ledum. 



Dytiscid^.. 



A gab us gochnanni Allied to the European A. dispar. 



COLYDIID^. 



Tarjjhius u'ollastoni A genus almost peculiar to the Atlantic islands. 



Elaterid^. 



Heteroderes azoricus Allied to a Brazilian species. 



Elastrus dolosus Belongs to a peculiar Madagascar genus ! 



Melyrid^. 



Attains miniaticollis Allied to a Canarian species. 



Rhyncopiiora. 



Plilmophagus variabilis Allied to European and Atlantic species. 



Acalles droueti A Mediterranean and Atlantic genus. 



Laparocerus azoricus Allied to Madeiran species. 



Asynonychus godmanni A peculiar genus, allied to Bracliyderes, of the 



south of Europe. 



Neocnemis occidentalis A peculiar genus, allied to the European genus 



Stropliosomus. 



Heteromera. 



Helops azoricus Allied to H. vulcanus of Madeira. 



STAPHYLINIDiE. 



Xenomma melanocepliala ...Allied to X. fiUforme from the Canaries. 



This greater amount of speciality in the beetles than in the 

 birds may be due to two causes. In the first place many of 

 these small insects have no doubt survived the glacial epoch, 

 and may, in that case, represent very ancient forms which have 



