Kinsey: Gall Wasp Genus Cynips 
403 
survives, for I never have observed more than one adult emerge 
from a single cavity.” 
Decatoma flava apparently has only a single brood annually, 
but each of the two species of Eurytoma has a brood that 
emerges from the young galls from July 24 to August 1, and 
a brood that does not emerge until the middle of the following 
June. “After the parasites have destroyed the host, it is ques- 
tionable whether they feed on the plant tissue, since the lining 
of the cavity they inhabit turns brown, becoming hard and 
brittle much earlier than is the case with the cavities occupied 
by Dryophanta erinacei” 
Of 1050 galls which this observer examined, sixty per cent 
[of the galls or larval cells?] were parasitized. I have found 
a similarly high percentage of parasitism in material from 
several localities, but in more than a thousand galls from Big 
Stone Gap, Virginia, and many hundreds of galls from each of 
a dozen other localities I found a parasitism which I should 
roughly estimate as not more than five or ten per cent. Altho 
I have at times published data on the percentage of parasitism 
of cynipid galls, I have come to believe that the conditions 
vary so greatly in different localities and in different seasons 
that it will be difficult ever to arrive at an estimate that will 
fairly represent the amount of parasitism normal for any 
species. 
Triggerson studied Synergus erinacei , finding it present in 
these galls not only as a guest but as a parasite which fed di- 
rectly on the larvae both of the gall maker and of the parasites. 
On eight occasions Triggerson fed gall maker and chalcidid 
larvae directly to the Synergus larvae, altho only once was he 
able to feed them larvae of their own species. The inquiline 
even mines from cavity to cavity of the polythalamous galls. 
It is to be questioned whether such mining is primarily in 
search of food or an evidence of primitive, phytophagous be- 
havior such as was probably the ancestral right of the Cyn- 
ipidae. Triggerson observed over eighty instances of such 
mining by this Synergus. “The average time required by 
Synergus erinacei to consume a larva was 1% hours.” This 
insect was found to have two broods each year, the larvae of 
the broods differing in some respects, but the observer did not 
record whether there is anything in this inquiline that ap- 
proaches the heterogeny of so many of the gall making species. 
