120 
Psyche 
[June 
2.0 times as wide as high. Front narrow, middle interocular distance 
•55"-57 times transfacial distance; middle interocular distance 1.25- 
1.30 times lower interocular distance, upper interocular distance 1.13- 
1.20 times lower. POLrOOL about as 6:5. Third antennal seg- 
ment 1. 5- 1. 9 times as long as thick, sometimes barely shorter than 
fourth segment. Subgenital plate roundly elevated medially; geni- 
talia as shown in Fig. 1. 
Distribution. — Northern Argentina, Paraguay, southern Brazil. 
Specimens examined. — 10 ?$, 4 cf c?. Argentina: i ?, Volcan, 
Jujuy, 2500 meters, 4 Dec. 1964 (C. C. Porter) [MCZ]. Para- 
guay: 1 $, Villa Rica (F. Schade) [MCZ]. brazil: 8 ?$, 4 c? d\ 
Nova Teutonia, Santa Catarina, Oct. — March (F. Plaumann) 
[MCZ, Coll. G. R. Ferguson]. 
Remarks. — The specimen from Jujuy is from a considerably 
higher altitude from the others, and is the only female studied which 
has black hairs on the scape and on the front and vertex; this speci- 
men also has the pale pubescence somewhat reduced, that on the 
front tending to form streaks along the sides and along the median 
sulcus, as in the Chilean species jaffneli. With respect to pubescence 
and pilosity, this specimen seems to occupy an intermediate position 
among the three species (as it does geographically), but in all struc- 
tural characters it agrees very well with specimens of bergi from 
lower and more easterly localities. 
2. Aridestus porteri new species 
Holotype. — $, PERU: Cuzco, 3800 meters, Sept. 20 — Oct. 2, 
1964 (C. C. Porter) [MCZ, No. 31,182]. 
Description of female type. — Length 12 mm; fore wing 9 mm. 
Head and thorax black, rendered somewhat bluish by the wholly 
dark pubescence; abdomen rufous, only the extreme base of the first 
segment and extreme tip of the apical segment infuscated; wings 
fuscous, violaceous, fore wing distinctly darker in a broad band along 
the outer margin. Head rather densely dark-haired, including the 
scape; propleura hairy; pronotum, front coxae, and lower part of 
mesopleura (in front of middle coxae) with a few dark setae. Clypeus 
2.2 times as wide as high. Front of moderate breadth, middle in- 
terocular distance .58 times transfacial distance; upper interocular 
distance .93 times lower interocular; POL and OOL subequal. 
Third antennal segment 3.0 times as long as thick, equal to .56 
times upper interocular distance. Transverse rugae of propodeum 
strong, the more posterior ones extending all the way to the ridge 
separating the propodeum from the metapleura. Fore basitarsus with 
