THE OCCURRENCE OF FORMICA CINEREA 
MAYR AND FORMICA RUFIBARBIS 
FABRICIUS IN AMERICA.! 
WILLIAM MORTON WHEELER. 
IN a valuable paper published in 1886? Dr. Gustav Mayr 
recorded both Formica cinerea and F. rufibarbis, two well- 
known European ants, as occurring in the United States. 
The former was cited from California and New Mexico, the 
latter from Colorado, Nebraska, California, and Montana. 
Seven years later, when Professor Emery published his impor- 
tant revision of the North American Formicidz,? he was so 
doubtful of the occurrence of these forms in the United States 
that he did not include them in his synoptic table. Concern- 
ing the former species he wrote : “ F. cinerea does not occur in 
North America; the form identified as such by Mayr will 
be described below as F. pilicornis n. sp." In regard to F. rufi- 
barbis his statements are less positive: ‘For the present I 
am inclined to doubt whether forms belonging to the true 
Jusco-rufibarbis series are actually indigenous to America. I 
am really unable to distinguish from rather pale and very pilose 
European fusca (fusco-rufibarbis) only three workers which 
were received from Colorado through Mr. Pergande. The 
precise locality of these specimens is not given." 
More than a year ago Dr. Harold Heath of the Leland Stan- 
ford University sent me numerous specimens both of F. cinerea 
and F. rufibarbis which he had kindly collected for me near 
San Jose, California. The F. rufibarbis was compared with 
1 Contributions from the inii Laboratory of the University of Texas, No. 38. 
2 Die Formiciden der Verei Staaten von Nordamerika,, Verhand. Zool.- 
Bot. Ges. Wien., Bd. xxxvi (1886), pp. 419-464. 
8 Beiträge zur Kenntniss der nordamerikanischen Ameisenfauna, Zool. Jahrb., 
Abth. f. gale ric - oo pp. 633-682, Taf. XXII, and Bd. viii (1894), 
PP- 257-360, T: 
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