MEXICAN FORMICIDyE. 859 



stri«. Pubescence yellowish, the erect hairs rather coarse 

 and sparse, most dense on the abdomen; antennse and 

 legs without erect hairs. Appressed pubescence most 

 dense on the head, antennae and legs. 



Color of the head, antenna and thorax brownish -yel- 

 low, the abdomen somewhat darker brown, with the su- 

 tures paler. Clypeus, mandibles and legs paler yellow, 

 the femora often more or less distinctly dusky. 



Five specimens. Tepic, Mexico. 



2. Prenolepis longicornis (Latr.) Roger. 



Formica longicornis Latreille, Hist. nat. Fourmis, 1802, p. 113. 

 Prenolepis longicornis Roger, Verz. d. Formiciden, 1863, p. 10. 

 For synonyms and references, see Dalla Torre, Cat. Hymenoptero- 

 rum, "vii, Formicidro, 1893, p. 179. 



Worker: Length, 3 mm. Head about twice as long as 

 broad, rounded behind, its sides nearly parallel. Cly- 

 peus strongly convex and with a rather sharp median 

 carina. Mandibles narrow and with about four or five 

 acute teeth. Antenna very long and slender, the scape 

 about three times the length of the head. Thorax elon- 

 gated, slender; dorsal surface of the pro-mesonotum 

 slightly arcuate, the suture dividing them nearly obsolete; 

 metathorax slightly elevated posteriorly, gently and uni- 

 formly arcuated and furnished each side, above the cox^, 

 with a small conical tubercle. 



Scale stout, narrow, slightly broadest at apex. Abdo- 

 men ovoid, pointed posteriorly. Legs long and slender. 

 Pubescence whitish; erect hairs coarse and rather sparse; 

 a few semi -erect hairs on femora and tibiae; appressed 

 pubescence observed only on legs and antennae. Head 

 and body polished and faintly shagreened. 



Color black, with a bluish reflection on the head and 

 thorax; scape and legs black or brownish; palpi whitish ; 

 tarsi and posterior margin of the abdominal segments yel- 

 lowish or brownish. 



