Scapes of antennae extending beyond the upper 
margin of the head less than one-third their 
length; scale of petiole with a broad median im. 
1S ee rl ae 17. Prenolepis 
19. Clypeus longer, as in Fig. 14D, with a slight mesal 
crest or angulation for most of its length 
MR a ayn 14. Formica 
Fig. 17.—Tarsal claws of 
army ants. <A, Labidus; B, 
Newamyrmex. (After M. R. 
Smith, courtesy of American 
Midland Naturalist) A B 
13 
Clypeus shorter, as in Fig. 14C, without a mesal 
crest but with an indistinct transverse swelling 
CAR ues ae ace lee See eT Wel eee 13. Lasius 
Subfamily PSEUDOMYRMECINAE 
2U, 
Includes only one genus in North America 
Pp Ct a Sey NE 5) oly Ec 19. Pseudomyrmex 
Subfamily MYRMECINAE 
21% 
an 
Head with dorsolateral projections (Fig. 23) ...22 
Head without dorsolateral projections (Fig. 15B) 
Bes AE ee SGA Oe ES Ae ee ee 23 
Head with long scrobe and several small tubercles 
(Pigs! SAtand 238) 5...) 21. Trachymyrmex 
Head with short scrobe and no tubercles (Fig. 
OO AD tteMAra ck Cnet re eye a CN 20. Atta 
{ 
/, 
i 
a) 
<M) 
yy 4 
} . 
| Ie ; 
AD Si 
paid 
mu 
Cc 
Fig. 18—The Argentine ant, Iridomyrmex humilis. A, wingless female; B, worker; C, male; D, immature stages: a, eggs; b, 
ing larva; c, full-grown larva; d, pupa, side view; e, pupa, ventral view; f, pupa, dorsal view. All about 12 times natural size. 
