20 
Psyche 
[March 
and transverse yellow bands on the abdomen (both models and 
mimics). Males of Austro chares gastricus in western Argentina also 
often have a partially or wholly rufous head (Fig. i), as in ruficeps 
Schrottky (Fig. 3), a member of the Polybia occidentalis complex 
which is common in that area. Still others have reduced pronotal 
and abdominal banding, as in scutellaris White, another member of 
this complex. Since various members of the occidentalis complex 
range all the way from Mexico to Patagonia, the complex may pro- 
vide models for several species of Austrochares of more restricted 
range, and it appears that gastricus , at least, is polymorphic in color, 
using at least three members of the complex as models. Similar color 
patterns also occur in several species of Mischocyttarus and other 
social Vespidae. Obviously the problem is complex and worthy of 
much more study. 
One of the most interesting aspects of mimicry in Austrochares 
is that only three of the five species have males which share the color 
pattern of social wasps ; the remaining two are not sexually dimorphic 
in color. The two which are not dual mimics ( elsinore and chilensis ) 
occur in areas where members of the Polybia occidentalis complex 
are rare or absent (coastal Peru and Chile), while the three species 
which have mimetic males occur in areas of great abundance of 
occidentalis and related species. Actually only mexicanus and gastricus 
are known to be dual mimics, since exiguus Banks is known only from 
the type male. However, the close resemblance of this male to that 
of mexicanus and gastricus leads me to believe that the female will 
also prove to be similar to those species. 
The case of Austrochares gastricus is especially interesting. This 
species has been regarded by Banks and others as occurring in both 
Argentina and Chile, but several authors have remarked that no 
Argentinian males have ever been found (although Chilean males 
are common enough). Only Brethes (1913) hit upon the truth when 
he suggested that Holmberg’s “male” species autrani might go with 
gastricus or a similarly colored species. I regard autrani as in fact the 
male of gastricus , a species occurring east of the Andes and showing 
strong mimetic dimorphism. The Chilean “gastricus” is here de- 
scribed as a new species, which is not dimorphic. The association 
of autrani with gastricus is supported by the fact that both sexes bear 
a strong resemblance to mexicanus, the two sexes of which were 
associated several years ago. Banks (1947) assigned the males of 
two of the species of Austrochares to “Batazonus” , i.e., P oecilopom- 
pilus, but they do not belong there. Most species of Poecilopompilus 
