464 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
Subopaque. Head regularly, rugosely punctate, each puncture 
bearing a short, recumbent glistening white hair. Cheeks and 
clypeus rugulose. Mandibles shining, coarsely punctured. Anten- 
nae densely punctulate. Thoracic dorsum finely punctate; pleurae 
shining; prothoracic pleurae densely punctate, meso- and epinotal 
pleurae rugose. Node shining, rugose. First gastric segment densely, 
irregularly striolate, the striolae longitudinal in front and transverse 
at the posterior border; remaining segments very densely striolate 
longitudinally. Legs somewhat shining, punctate. 
Thorax and gaster finely pubescent and with scattered erect hairs. 
Legs sparsely pilose. 
Color black; eyes, inner border of mandibles and tarsal joints red- 
dish. Pilosity brownish. 
Described from several workers taken at Abunda. 
The curious structure of the petiole distinguishes this from the 
other species of the subgenus. 
161. Dolichoderus (Monacis) debilis Emery. 
Several workers from Madeira-Mamoré Camp 37 agree closely 
with cotypes received from Professor Emery. 
162. Dolichoderus (Monacis) debilis Emery var. rufescens Mann. 
The single colony of this very distinct variety was found at Madeira- 
Mamoré Camp 39, living parabiotically with Odontomachus affinis 
subsp. mayi. It differs from D. debilis in color, the greater length of 
the petiolar spines, and the coarse cephalic sculpture. 
163. Dolichoderus (Hypoclinea) abruptus (F. Smith). 
Many specimens were taken at Porto Velho, Abunda, and Madeira- 
Mamoré Camp 41. The workers were found most frequently on 
shrubs, where they attended Membracidae. 
164. Dolichoderus (Hypoclinea) lugens Emery. 
This species, originally described from Bolivia, swarmed in certain 
parts of the forest near Porto Velho, and at Abuna, Brazil and Bolivia. 
It forages on the ground more than do the other species of the genus, 
