16 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 68 



Fontanelle opening projected into a very short tube near front 

 of head. Post-clypeiis short, not raised. Labrum light castaneous 

 brown, 3 lobed at apex, center lobe hyaline, with long hairs at 

 apex. 



Mandibles piceous, shining, elongate, slender, with stout reddish- 

 brown base (few long hairs at the base), incurved and pointed at 

 apex, marginal teeth as in figure. First marginal tooth on left 

 mandible sharp pointed, near middle of mandible ; mandibles longer 

 and more slender than in chaquimayensis ; marginal teeth nearer 

 apex than in snyderi; marginal tooth on right mandible about sam.e 

 size as that on the left, just below it — slightly nearer the base. 



Antenna reddish-brown, broken, 18+ ? segments, pubescent ; third 

 segment subclavate, longer than second or fourth; segments become 

 more elongate and slender toward aj^ex. 



Pronotum yellow-brown with margins reddish, saddle-shaped; 

 lateral spines are shorter than in dims, snyderi, or chaquimay ens-is ; 

 also those on meso and meta-nota are shorter. 



Legs yellow-brown, tibiae darker, elongate, with long hairs. 



Abdomen light castaneous brown, densely covered with light 

 yellow, long hairs. 



Measurements. — 



Total length of soldier, 15-17 mm. 



Length of head with mandibles, 9.9-10.0 mm. 



Length of head without mandibles (to tip labrum), 8.15-S.4 mm. 



Length of head without mandibles (to anterior of head), 7.0-7.1 mm. 



Length of labrum (to base central hyaline lobe), 1.1-1.2 mm. 



Length of pronotum, 1.6 mm. 



Length of hind tibia, 6.75 mm. 



Length of left mandible, 3.5-3.8 mm. 



Width of head (at broadest point), 6.9 mm. 



Width of labrum, 1.5-1.6 mm. 



Width of pronotum (to tip of spines), 4.45-4.5 mm. 



The soldier of /S. peruanus is close to S. emersoni Snyder but is 

 slightly darker colored and the marginal teeth on the mandibles 

 are longer in peinianus and are arranged differently and there are 

 other differences in the size of the pronotum and the width of head. 

 The lateral spines on the thorax are longer in emersoni. 



Described from two soldiers kindly presented to the U. S. National 

 Museum b}'' Dr. A. Emerson from a series in the Carnegie Museum, 

 Pittsburgh, Pa.— Ace. No. 4043 collected on October 9, 1909, at Villa 

 Bella, Bolivia. 



The species is known from both winged adults and soldiers and 

 occurs in Peru and Bolivia. 



