1979] 
Petralia & Vinson — Anatomy of Ant Larvae 
381 
an almost semicircular arrangement on each segment, with anterior 
spinules pointing posteriorly and lateral spinules pointing medially 
(Fig. 7). A similar arrangement of spinules is found on the remaining 
abdominal segments anterior to the anus. However, on these seg¬ 
ments the concentric circle of short rows of spinules is complete, 
including posterior spinules which point anteriorly (Figs. 8, 9). 
PONERINAE, ODONTOMACHINI 
Odontomachus clarus — (Figs. 10-12). Neck attenuated as in the 
Ponerini (Fig. 10). Ventral body region bears only a few small, simple 
hairs. This region is flanked laterally by elongate cone-shaped pro¬ 
tuberances (which continue onto the dorsal surface) bearing 4-6 long 
simple hairs near the apex (Fig. 10). Numerous rows of posteriorly 
pointing spinules occur medioventrally on at least the first 8 body 
segments (Figs. 11, 12). The ventral surface of the prothorax also 
bears a pair of fleshy tubercles anteriorly. 
PSEUDOMYRMECINAE 
Pseudomyrmex pallidus — (Figs. 13, 14). The structure and vesti- 
ture of the trophothylax are similar to those in P. g. mexicanus 
although in the specimen examined, the trophothylax was tear-drop 
shaped in longitudinal section and the segments were indistinct. 
Pseudomyrmex gracilis mexicanus — (Figs. 15-17). The tropho¬ 
thylax is well developed. It is formed from the inverted ventral 
surfaces of the thorax and 1st 2 abdominal segments. The surface of 
the trophothylax bears numerous rows of spinules (Figs. 15, 16). 
Spinules on the thoracic and 1st abdominal segments point towards 
the posterior boundary of each segment (Fig. 15); those on the 2nd 
abdominal segment point towards the anterior boundary of this 
segment. The latter spinules cover the posterior lip of the tropho¬ 
thylax. The posterior portion of the 2nd abdominal segment, as well 
as the succeeding segments, bears numerous, straight, simple hairs 
(Fig. 16). In specimens where part of the trophothylax is extruded, 
the spinules on the extruded region point posteriorly (Fig. 17). The 
lateral lips of the trophothylax bear spinules pointing medially (Fig. 
17). 
MYRMICINAE, MYRMICINI 
Pogonomyrmex barbatus — (Figs. 18-21). The thorax is attenu¬ 
ated (Fig. 18). Ventral body region bears numerous medially pointed 
hairs, most of which are denticulate on the distal half. Numerous 
posteriorly pointing spinules in short rows occur on the ventral 
region of the thorax and 1st abdominal segment. Numerous short 
