1934 ] 
Three New North American Ants 
197 
the character of an introduced species but is not easy to ex- 
plain in the case of a native form. 
All of the above evidence is, of course, negated by the dis- 
covery of an American species of Anergates. Under these 
circumstances to continue the belief that Tetramorium cse- 
spitum is an introduced ant necessitates the assumption, 
that when introduced a nest of csespitum contained speci- 
mens of Anergates and since the time of introduction 
Anergates has undergone sufficient change to rank as a 
separate species. The author finds neither point tenable 
and is therefore prepared to regard csespitum as a na- 
tive member of our North American ant fauna. This 
bears out evidence presented by two of Emery’s earlier 
records for csespitum, one from Tennessee, the other from 
Nebraska. These records were always troublesome to the 
older view of csespitum as an introduced species since both 
lie well beyond the eastern range of the ant and are separ- 
ated from it by areas in which csespitum apparently does not 
occur. Such a distribution need occasion no remark in the 
case of a native form. 
One additional point may be considered here. It is possi- 
ble that the insect which we now regard as the North Amer- 
ican representative of Tetramorium csespitum may not be 
cospecific with the European form. As far as the author 
can ascertain there are no differences of specific significance 
but since csespitum shows a number of variants in Europe 
it is difficult to make a positive statement in this regard. 
However, even should the North American Tetramorium 
prove identical with one of the European forms of csespitum 
its status as a native ant remains unaltered. One need only 
cite the case of Formica fusca to furnish an example of a 
holarctic host which supports specifically different parasites 
in the Old and New Worlds and whose distribution cannot 
possibly be the result of introduction. 
ECOLOGICAL NOTES. 
(1) An unusual slave of Formica sanguinea subsp. puberula 
Emery. 
