402 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
antennal scapes are short and broad. There was only a small number 
of workers together and all but three escaped. 
2. Paraponera clavata (Fabricius). 
Found commonly at Pard, Manaos, and along the Rio Madeira 
at Abunda, Porto Velho, and Camps 39 and 41. 8 Q. 
Next to Dinoponera grandis Guérin, this is the largest of the Brazil- 
ian ants. It is much more widely distributed than D. grandis, occur- 
ring from Central America to Paraguay. In habit it is diurnal. The 
colonies are composed of a small number of individuals, which nest 
in the ground, generally among the roots of trees or shrubs. 
3. Platythyrea angusta Forel. 
A series of workers from Porto Velho, Abundé, and Madeira-Mamoré 
Camp 39 agrees well with the description, but have the anterior femora 
much swollen at the base. Dr. Forel recently showed me the type, 
which also has enlarged femora. This species, originally described 
from Trinidad, is more slender than the other South American forms, 
and the petiole is twice as long as broad. These characters, and the 
structure of the femora distinguish it from the others. 
4. Platythyrea incerta Emery. 
A single worker from Madeira-Mamoré Camp 41 agrees closely 
with Emery’s description. It differs from P. punctata in being much 
larger (length 8 mm.) and in having the head shorter and the punc- 
tuation considerably coarser. 
5. Platythyrea meinerti Forel. 
Plate 1, figs. 2, 3; Plate 7, fig. 53. 
A colony of this species was found at Para in one part of a termite 
nest, a favorite nesting place of the genus, which is probably largely 
termitophagous in habit. This species is characterized by the strongly 
bisinuate petiolar node and the large eyes, which are as long as their 
distance from the anterior border of the head. A full-grown larva is 
shown Plate 7, fig. 53. 
