GEOLOGICAL RECORD. 53 



as at the present day, that it seems probable they must have 

 existed as far back as in the Trias, though they have not left any 

 remains. Of the six hundred species of Tertiary Hymenoptera 

 enumerated by Handlirsch, more than half are ants, representing a 

 considerable number of genera many of which are still living. 

 Tertiary ants have occurred in twenty-three localities in Europe 

 and North America ; only one of these localities Bembridge in 

 the Isle of Wight being situated in Britain. 



The remains of three genera Myrmica, Formica and Cam- 

 ponotus were found in the Bembridge limestone ; the occurrence 

 of the last-mentioned genus is of considerable interest, as no 

 species of Camponotus is living in our country to-day. 



The largest number of Fossil ants have been found in the Baltic 

 and Sicilian amber, and the beds of Radoboj, Oeningen, and 

 Florissant. 



Emery considers that the study of the ants of the Baltic and 

 Sicilian amber proves that the Arctic fauna went down from the 

 North as a host of conquerors. 



Wheeler shows that of the forty genera found in these ambers, 

 thirteen are extinct, and twenty-seven, or more than two-thirds, 

 are still living ; moreover, some species of the Baltic amber are 

 almost, if not quite, identical with living species. 



Emery accounts for the poverty of the European ant-fauna as 

 follows : " My studies on the ants of the Sicilian amber have de- 

 monstrated that at the beginning of the Tertiary, Europe had 

 an ant-fauna of Indoaustralian character, still living and exclu- 

 sively of this character in Sicily during the formation of the amber ; 

 while to the north of the sea, which at that time extended across 

 Europe, representatives of this fauna, mingled with Formica, 

 Myrmica and other recent holarctic types, lived in the forests of 

 the Samland. After the disappearance of this sea the northern 

 fauna pushed its way southward as far as the Mediterranean. Then 

 came the Glacial epoch, which extinguished the Indian fauna in 

 the north and drove its feeble remnants, mingled with arctic forms, 

 to the warmer localities of southern Europe. From these regions 

 the present ant-fauna wandered back, with the disappearance of 

 the ice, into the middle and northern portions of the continent. 

 But the tropical forms had difficulty in returning, because the 

 Mediterranean, the African deserts and the steppes to the eastward 

 were so many barriers to their progress. The European ant-fauna 

 therefore remains comparatively poor " (Wheeler's translation). 



The reader who wishes to study more closely the palaeontology 

 of ants is referred to the works of Er. Andre, Emery, Handlirsch, 

 Heer, Mayr, and Wheeler. 



