WlfEEJ.ER—ANTS FROM .UOr.Vr If.lS/Z/RCFROX 
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In the study of mountain faunas it is well to bear in mind what Forel says 
in his work on the ants of Switzerland*: “One should never judge of the habitat 
of a species from the elevations at which isolated males or females have been 
captured. We have, in fact, observed that these se.xes always seek the summits 
for the purpose of mating. On a beautiful day in summer, they often alight in 
regions where their species cannot subsist, and where they soon perish. Thus M. 
bugnion found males of /n.'/'w/o? and /z'<r/£7/.f/r on the Hiifi Glacier and he 
brought me specimens of these ants from the summit of the Stiitzerhorn 
(Orisons). 1 have myself taken males and females of these ants on the snow- 
covered ridge which separates the Kngadine from the valley of Roseg between 
the Piz .Surlei and the Piz Corwatsch. Now neither the formicaries of ru/a nor 
the formicaries of pratcnsis are found above the region of pines, whereas the 
winged individuals just mentioned had ascended to that of the eternal snows. 
Hence a female Mvnnecina LatreiUci which I took at a considerable elevation in 
the Jura near Mont 'I'endre does not prove to me that the formicaries of this 
species subsist at such an altitude.” 
The absence of ant colonies on the summit of Mount Washington is to be 
attributed to the length and rigor of the winter at such an elevation. In the 
Rocky Mountains colonies are very abundant up to an altitude of 9000 to 10,000 
ft. and may be found even as high as timber-line between 11,000 and 12,000 ft. 
I have observed this distribution on Pike’s Peak, near Cripple Creek, and on the 
neighboring mountains. Verv similar conditions seem to prevail in the Hima- 
layas. 
Hare, cold mountain tops thus appear to be a source of “catastrophic elimi- 
nation” to those winged seeds of their species, the female ants. ( )ther sources 
of such elimination are torrential showers occurring during or just after the 
marriage flight; many birds, which are fond of eating winged ants; and drown- 
ing, as the result of long flights out to sea or over our Great Lakes. During the 
summer months the insect drift which is cast up on the beaches of Lake Michi- 
gan and Lake Superior sometimes contains thousands of dead female ants. 
Other less important agents of destruction are some of tire solitary wasps 
that provision their nests with female ants captured during or just after the mar- 
riage flight. Aphilanfhops frigidus, for e.xample, has been seen to capture and 
carry home our common /'hr-w/ViryV/.fo? var. jvr/wf/vcdvr. .Mr. H. L. Viereck has 
sent me specimens of these wasps collected together with their prey by Mr. 
Morgan Hebard in Haraga County, Michigan. When we add to these destructive 
*I.es Foiirmi,s cie la Suisse, /.iiricti 1S74, p. 21 1. 
