The Ants of the Baltic Amber. 



By 



William Morton Wheeler Ph. D. 



Professor of Economic Entomology, Harvard University. 



Seven years ago the late Professor Richard Klebs of Konigsberg 

 requested me to study and describe the ants in his beautiful collection 

 of amber inclusions, and, on my consenting, forthwith sent me all of 

 his specimens, 1405 in number. A year later Professor A. Tornquist 

 generously sent me the entire Formicid collection of the Konigliche 

 BernsteinsammluDg des Geologischen Instituts of Konigsberg. This 

 remarkable collection comprises 7819 specimens, exclusive of Gustav 

 Mayr's types, which were also loaned me for reexamination. In addition 

 to this material I have been able to study three smaller collections. 

 Monsieur G. Seyerin loaned me the collection of the Brussels Museum, 

 comprising 19 specimens, Dr. Richard Heymons that of the Berlin 

 Museum, comprising 115, and Mr. William Haren of St. Louis, Missouri, 

 his private collection of 169 specimens. Thus I have been able to 

 study altogether 9527 ants from the Baltic amber. I wish to express 

 my indebtedness to all these gentlemen for the loan of so many speci- 

 mens, and, especially to Prof. Tornquist for permission to retain so 

 much valuable material in my possession for several years. I sincerely 

 regret that the work has been so unduly protracted and so frequently 

 interrupted by urgent professional duties. This regret is the deeper, 

 because Prof. Klebs, who first interested me in the subject and gave 

 me much friendly assistance in the early part of the work, did not 

 live to see it completed. 



As many previous students have remarked, the study of the 

 insects embedded in the amber is frought with many and peculiar 

 difficulties. Although some specimens are as beautifully clear as if 

 they had just been carefully dehydrated and embedded in Canada 

 balsam by an expert histologist, most of the specimens are either in 

 awkward positions or have portions of the body concealed beneath 

 milky or silvery films or air-bubbles or obscured by disconcerting 

 cracks, or the highly refractive medium gives rise to distorted images 

 which can be corrected only by repeated examination in the most 

 various lights or by careful comparison of numerous specimens of the 

 same species. It is, of course, possible to dissolve the amber away 



Scbriften d. Physikal.-okonom. Gesellscbaft. Jabr^ang LV. 1 



