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Indiana University Studies 
Neuroterus haccarum 
bisexual form haccaiutm Linnseus 
agamic form lenticularis Olivier 
Neuroterus numismalis 
agamic form numismalis Olivier 
bisexual form vesicatrix Schlechtendal 
Neuroterus Ixviusculus 
agamic form Iseviusculus Schenck 
bisexual form albipes Schenck 
Some other European species may belong here, but where 
I lack sufficient material, I prefer to withhold opinions as to 
generic assignments. At least the first three of my list should 
be considered varieties of one species, haccarum, if the scheme 
I employ for American Cynipidse is to be extended. This 
interpretation will help explain, particularly to European 
entomologists, what I am considering as varieties. 
The subgenus is probably restricted to the Old World, 
its only near American relative being Neuroterus {Neo- 
spa.theg aster) vesicula, and the differences between these two 
groups are many. 
Life histories are known for all of the insects listed here. 
In every case the agamic generation is a fall and winter 
development, the insect emerging early in the spring; while 
the bisexual generation matures rapidly in the spring, emerg- 
ing in late spring or early summer. The insects of the two 
generations do not differ greatly, except in regard to their 
methods of reproduction, the shape and size of the abdomen, 
and the development of the ovipositor. The morphologic 
differences are readily ascribable to the differences in modes 
of reproduction and places of oviposition. In practically all 
Cynipidse the agamic eggs are larger and the abdomen of 
the agamic female larger than in the bisexual female. The 
galls of the two generations are very similar, differing how- 
ever in details of form, indicating some degree of more 
specialized heterogeny than is known for any American cyni- 
pid. But in fundamental nature, the heterogeny of 
Spathegaster is primitive, and entirely understandable as an 
extreme development of seasonal dimorphism. 
In general European workers placed the bisexual forms 
more often in Spathegaster and the agamic forms in 
