MANN: THE ANTS OF BRAZIL. 423 



near apex, then incrassate; funicular joints a little longer than broad. 

 Eyes distinct, convex. Pronotum twice as long as broad, flat above, 

 the lateral borders elevated into a rounded ridge, which is somewhat 

 thickened at middle. Mesonotum separated from pronotum by a 

 transverse ridge, elevated, concave at middle, strongly margined at 

 sides; mesial to the margin is a longitudinal furrow and on the upper 

 surface two parallel ridges. Base and declivity of epinotum subequal 

 in length, the former flat above with margined sides; surface of the 

 latter evenly convex. Petiole from above longer than broad; flat 

 above, with straight, roundly margined sides. Postpetiole a little 

 longer than broad, broadest behind, rounded above and at sides, 

 anteroventral surface with a distinct tooth. 



Head, antennae, thorax, and epinotum sublucid; coarsely, granu- 

 losely punctate, throughout, except for a rounded area mesial to the 

 eye, which is finely punctate. Antennae, mandibles, petiole, post- 

 petiole, and legs more shallowly punctate. Gaster smooth and shining. 



Head, body, antennae, and legs with long erect hairs; funiculus 

 pubescent. 



Color black, antennae, and legs dark reddish brown. Pilosity 

 yellow. 



Described from several workers taken from a file that was running 

 beneath the loose bark of a felled tree at Madeira-Mamore Camp No. 

 39. This is a very distinct form because of its peculiar sculpture and 

 the strong carinae on the thorax. The latter, especially those at the 

 middle of the mesothorax, are interrupted so that in profile they ap- 

 pear as tubercles. 



Myrmicinae. 



63. Pseudomyrma arboris-sancti Emery. 

 Plate 3, fig. 21. 



This species is widely distributed in northern South America, and 

 many observations have been made on its relations to the trees of the 

 genus Triplaris with which it appears to be always associated. The 

 tree is well known to the Brazilians and Bolivians by the name of 

 "palo santo," and the ant is called the "taschi." I was told that no 

 living tree was ever without the ants and that the ants never nested 

 elsewhere than in this plant. At Madeira-Mamore Camp 43 

 Triplaris was fairly common in the woods and I examined some 



