The Ants of the Baltic Amber. l\ 



Pheidologeton, Oligomyrmex and Carehara). This explains why Mayr 

 originally described E. antiqua as a Pheidologeton, and why Emery 

 later assigned it to Aeromyrma, after he had discovered a species of 

 this genus (A. sophice) in the Sicilian amber ^). It is, indeed, not 

 improbable that species of Erehomyrma may still exist in the Old 

 World tropics, just as a species of Carehara has recently been discov- 

 ered by Santschi to occur in South America. The case of Ereho- 

 myrma antiqua thus bears an interesting resemblance to that of the 

 Cicindehd beetle Tetracha Carolina L. Until recently this insect was 

 supposed to belong exclusively to America, where it ranges over the 

 southern United States, Central America, West Indies and South 

 America (Chili and possibly Argentina), but Horn ^) has discovered 

 a specimen of it in the Baltic amber. He regards the species of 

 Tetracha, and especially T. Carolina, as among the most ancient and 

 primitive of the Cicindelidae, and it is clear that it must, like Ereho- 

 myrma, once have inhabited the eastern hemisphere. In order to 

 account for its occurrence in the amber he resorts to the following 

 hypotheses: ,,Wie die Bernstein- Te^rac/m nach dem preuBischen Sam- 

 land gewandert ist, bh ibt eine andere Frage. Zwei Wege waren 

 moglich : I. der eine direkt von Afrika aus (vielleicht iiber die 

 egyptische Landbriicke oder ostlich davon, um dann auf dem umge- 

 kehrten Weg von II nach Amerika zu gelangen); II. von Amerika 

 aus iiber die nearktische und skandinavische Landmasse, was mir 

 zum mindesten nicht unwahrscheinlich erscheint." It is clear that 

 one might advance similar suppositions in regard to Erehomyrma, but 

 for the present I deem it unnecessary to go beyond the facts, which 

 show that both Tetracha and Erehomyrma were cosmopolitan genera 

 during the Eocene and that their present restriction to the neotropical 

 region is due to their later extinction in the Old World. A similar 

 statement would probably cover many, if not all, of the cases of sup- 

 posedly close nearctic and neotropical affinities among the insects of 

 the Baltic amber. 



Having thus excluded the ant-faunas of Africa and America from 

 any demonstrable participation in the composition of the amber fauna, 

 except in so far as these countries have several genera in common 

 with the Eurasian continent, we may turn to a consideration of the 

 relationship of the amber to the present Eurasian and Australian 



*) Le Forraiche deU'Amiira Siciliana, etc. loco citato, p. f)??. 



1) Uber das Vorkommen von Tetracha Carolina L": im prenSischen Bernstein 

 and die rhylogcnie der Ckindela - AxiGn. Deutsch. Ent. Zeitschr. 191)6. Heft II. 

 pp. 329—336. 



