WHEELER: ANTS OF THE GENUS FORMICA. 481 
yellow. In many specimens the upper surface of the head is more 
reddish than the remainder of the body but there is little difference in 
coloration between the smallest and largest workers. 
Type Locauity. — Massachusetts: South Natick (A. P. Morse). 
The position of this species is problematic, as the female is unknown, 
but the characters of the worker certainly ally it to the preceding 
forms of the microgyna group. It differs from all of these species in 
its peculiar color and sculpture, the greater convexity of the posterior 
portion of the head and the shape of the petiole. It must be a rare 
species as I have been unable to find it again, even with Mr. Morse’s 
assistance, in the type locality. 
Exsecta Group. 
66. EF. EXSECTOIDES EXSECTOIDES Forel. 
F. integra Mayr, Verh. Zool. bot. ver. Wien, 1862, 12, p. 70; Ibid., 1886, 36, 
p. 425, 9 & (nec Nylander). ° 
F. exsectoides (Forel) McCook, Trans. Amer. ent. soc., 1877, 6, p. 252-296, 
figs. 2-5, pls. 2-6; Proc. Acad. nat. sci. Phila., 1877, p. 185; Amer. natur., 
1878, 12, p. 481-345, 8 figs.; Proc. Acad. nat. sci. Phila., 1879, p. 154-156. 
F. exsectoides Forel, Ann. Soc. ent. Belg., 1886, 30, C. R. p. xxxviii, 8 9; 
Dalla Torre, Catalog. Hymen., 1893, 7, p. 195; Emery, Zool. jahrb. 
Syst. 1893, 7, p. 658, pl. 22, fig. 6; Wheeler, Bull. Amer. mus. nat. hist., 
1906, 22, p. 71, 403-413, pls. 43-48. 
Worker. Length 4.5-7.5 mm. 
Mandibles with the apical border 8-toothed, the basal border with 
two or three minute and often very indistinct or obsolete denticles. 
Head, excluding the mandibles as broad as long, a little narrower 
in front than behind, with deeply excised posterior and nearly straight 
lateral borders. Front convex, vertex flattened. Clypeus strongly 
carinate, with anterior border entire and angularly projecting in the 
middle. Frontal area distinct, frontal carinae moderately diverging. 
Antennae slender, scapes not thickened towards their tips, funiculi 
with the four basal joints somewhat longer and more slender than the 
penultimate joints. Maxillary palpi moderately long, 6-jointed. Pro- 
and mesonotum distinctly flattened above, mesoépinotal constriction 
rather shallow; epinotum with subequal base and declivity, each 
straight in profile and meeting at a rounded obtuse angle. Petiole 
high and broad, compressed anteroposteriorly, with flattened anterior 
and posterior surfaces, and sharp, cultrate border, which, seen from 
