— 175 — 
arcuatim transverse striato-rugosa; scutellum distinetum, 
laevigatum, transverso-toriforme; sutura scutello-metano- 
talis profunde impressa; metanotum  spinulis duabus 
ereclis, paulo extra curvalis, parte basali subtiliter  co- 
riacea, parte declivi sublaevigata, lateribus infra striatis; 
petioli rugulosi modus anticus transversus margine su- 
periore parum aut vix arcuatim emarginato, nodo po- 
stico transverso supra lateraliter rotundato; abdomen 
laeve. 
Operaria: Long. ?:3-2:7. mm. Rufa, nitida, abdomine 
nonnunquam nigricante; corpus totum longe et copiose 
pallide pilosum; mandibulae laevigatae punctis nonnullis, 
ad basim striatae; caput, thorace latius, disco laevigato 
punctis nonnullis dispersis, ad latera longitudinaliter ru- 
gulosum et postice rugulis nonnullis transversis; cly- 
peus longitrorsum striatus, in medio sublaevis; laminae 
frontales haud lorgae, longitudinaliter striatae, antice mo- 
dice dilatatae; genae striatae; pronotum antice subtiliter 
rugulosum, postice transversim arcuato-carinato striatum; 
mesonotum disco subcirculariter carinato-striato; scutel- 
lum rugulosum distinctissimum, triangulare et elevatum; 
sutura scutello-metanotalis profunda; metanotum subti- 
liter reticulato-punctulatum spinulis 2 erectis, paulo di- 
vergentibus; petioli nodi subtiliter et superficialiter 
reticulato-punctati ( coriaceo-rugulosi ), nodi antici margo 
superior rotundatus, nodus posticus Ref ne o abdo- 
men laeve. 
Inventun formicetum hujus speciei in locis urbi Buenos 
Atres propinquis; anno 1866. — Sr. 
