1929] 
Stylopized Vespidse 
273 
individuals are eventually found in most groups. We hope 
that the publication of this list will stimulate those in- 
terested in the taxonomy of the Vespidse to mention the 
stylopized examples contained in the collections they study. 
The Frequency of Stylopization 
The frequency of stylopization, then, varies from zero in 
certain groups to as much as 25% in particular collections 
of Polistes (Wheeler, 1910; Schrader, 1924). In our search 
for stylopized specimens we have kept some count of the 
frequency of their occurrence in several collections and in 
different taxonomic groups, and are able to give the follow- 
ing figures. Unfortunately we did not always make notes 
upon the frequency, and while the following numbers are 
proportionate, they do not represent our entire search. 
Vespidse of 16,932 specimens 157 stylopized, or 0.93% 
Masaridinse 256 
Raphiglossinse 8 
Zethinse 158 
Eumeninse 14,926 
Eumenes 1,651 
Odynerus s. 1. 4,316 
Monobia 271 
Montezumia 152 
Synagris 443 
Pterochilus 74 
Alastor 65 
Polybiinse 623 
Ropalidiinse 160 
0 0 % 
0 0 % 
4 “ 2.53% 
138 “ 0.92% 
11 “ 0.67% 
35 “ 0.81% 
4 “ 1.48% 
0 0 % 
0 0 % 
0 0 % 
0 0 % 
8 “ 1.28% 
2 “ 1.25% 
No records w T ere kept of the frequency of stylopized 
Polistes in collections because much more accurate data 
based on field counts are available for this genus (see 
Pierce, 1909, 1911, 1918; Schrader, 1924). 
In the American Museum of Natural History is pre- 
served a mud nest of Ancistrocerus birenimaculatus, and 
the twenty-two wasps which emerged from it. Five of these 
twenty-two wasps, or 22.7%, are stylopized; showing that 
the rate of parasitism in particular nests can be almost as 
