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[Vol. 89 
the V rufa species group, and V. squamosa, but is absent in queens 
of Dolichovespula and the V. vulgaris group (Landolt and Akre 
1979). The seventh sternal gland and associated brush are present 
and well developed in both species. The Dufour’s gland of V austri- 
aca is considerably larger than in most other yellowjacket queens 
(Fig. 3) and averaged 5.8 mm long (range = 4.8 - 7.5 mm, N = 15) 
and 0.5 to 0.8 mm wide. In contrast, this gland was less developed in 
V acadica (x = 2. 1 mm long, 0.3 - 0.5 mm wide) and other nonpara- 
sitic queens (Landolt and Akre 1979, 1.5 - 2.5 mm long). The same 
gland was found to be enlarged in the facultative social parasite V 
squamosa, as it was ca. 0.2 mm wide and 6 mm long (Landolt and 
Akre 1979). However, the most well developed Dufour’s gland is 
found in the other Nearctic vespine inquiline, D. arctica. One D. 
arctica female had a Dufour’s gland 14 mm long and 0.3 mm wide 
(Landolt and Akre 1979) and in two parasites dissected by Jeanne 
(1977) this gland was 12.8 mm and 27.2 mm long. In this study 
three, early summer, D. arctica parasites were found to have very 
long glands (16.5, 20.0, 20.5 mm) greatly folded around themselves 
and the alimentary canal. In these three parasites and 16 other 
preusurpation individuals the gland was flattened and did not con- 
tain any material in the lumen. In contrast, the gland was fully 
distended and filled with an oily substance in summer, preusurpa- 
tion V austriaca. It was empty and flattened in new fall parasites, 
while in the aged parasites the gland was only partially full and 
appeared collapsed. The gland contained a yellow oily substance in 
preserved specimens, but instead had a clear, oil-like material in 
three V austriaca specimens killed and immediately dissected. 
The ovaries consist of 12 ovarioles as do most Vespu/a and 
Dolichovespula (Kugler et al. 1976). The ovaries did not fill the 
entire gaster in the two aged parasites as they did in later summer 
foundresses of V. acadica. Preusurpation parasites and early 
summer host queens had a slight ovarian development with 1 to 6 
eggs greater than 1.0 mm in length and thus probably ready to be 
laid. Both species have six gastral ganglia. 
Discussion 
This study confirms the results of a previous morphometric analysis 
of V. austriaca (Eck 1979). Eck (1979) compared the inquiline with 
the European host, V rufa, and found that although both were 
