1955] 
Wilson and Broivn — Formica 
119 
face. As previously noted, this is a character subject to 
strong allometric variation. The subnuda types we have 
examined in the same size class as the emeryi syntypes 
(head widths 1.41 — 1.64 mm) exhibit the same head shape 
and eye placement, and this also holds for other subnuda 
series. 
(2) Wheeler and Creighton both have distinguished 
emeryi from subintegra (= pergandei) by the presence 
in emeryi of a shallow transverse groove on the dorsal 
propodeal face of the worker. In this case the wrong pair 
of species was being compared, but the character must 
also be considered with reference to subnuda. Of the 
four subnuda syntypes we have examined, three possess 
the character and one lacks it. Other subnuda and sub- 
integra series show the same strong intrandidal variation, 
and we are of the opinion that the propodeal impression 
is either an ecophenotypic character or else an artifact 
produced by warping when the specimens were first dried 
out. In any case, it is not diagnostic. 
(3) The genal borders of the emeryi syntype are nearly 
straight, and where they meet the curved occipital border 
near the lower margin of the eye a weak concavity is 
produced. This is not so common a feature of subnuda, 
but is nevertheless within the normal range of variation 
for the species. One specimen of a series from Magnolia, 
Mass., shows the “emeryi” contour on one side and the 
typical subnuda contour on the other. 
(4) The emeryi worker and queen syntypes actually 
differ the most from average subnuda in a character not 
mentioned by previous authors. The petiolar scale in side 
view is unusually thick for subnuda, approaching the 
usual subintegra condition, but even this is still within 
the range of continuous variation of subnuda as we con- 
ceive of that species. 
F. subnuda definitely has a more boreal distribution 
than does F. subintegra, though the ranges of the two 
species come into close contact and even overlap in regions 
such as eastern Massachusetts, part of Michigan, and in 
