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mark (E. B. Hoffmeyer coll.) from a locality about a hundred miles 
from the type locality of similis. 
PARASITE . — Platygaster instricator (acc. Hennequy 1904). 
Adler discovered this insect as a result of his experimental 
breeding from the agamic longiventris in the spring of 1880. 
He found the adults emerging from the galls in May, about 
two weeks before he secured adults of the bisexual form of 
folii in that same year. But since Adler’s single record seems 
to be the basis of all the other published emergence data for 
substituta, and since the Danish material in my collection 
(Hoffmeyer coll, and det.) is dated as late as May 31, June 2, 
and June 4 while taschenbergi distributes its emergence from 
May 25 to June 11 even in Denmark (not far from Adler’s 
locality in Germany), we are unwarranted in concluding (as 
previous literature does conclude) that there is any great 
difference in the emergence dates of the two insects. 
Adler saw substituta oviposit to give rise to the agamic 
longiventris only by an accident in connection with his experi- 
ments on the succession of taschenbergi and folii. In 1876 he 
placed what he took to be taschenbergi adults on the leaves of 
an oak from which he later secured galls of longiventris. His 
further work on longiventris having shown the very close 
similarity of both galls and insects of taschenbergi and 
substituta, we may conclude that Adler had really discovered 
the alternation of our present species. The data are, how- 
ever, scant enough to encourage some one in Europe to repeat 
the work. 
The gall of substituta is said (Adler 1881 and Hieronymus 
1890) to differ from that of taschenbergi in nothing more 
than the few characters which I have given above. Adler 
considered that the insects of the two could be distinguished 
by the leg coloration which T have noted (with corrections) 
above. Mayr (1882) put taschenbergi, fiosculi, similis, and 
verrucosa in a single paragraph with a remark about “Die 
hierhergehorenden Arten, welche ich nicht sicher zu unter- 
scheiden im Stande bin meaning that he was unable to 
distinguish these insects; but the Kieffer (1901) and Dalla 
Torre and Kieffer (1910) monographs arrive at the conclusion 
that these bisexual insects are indistinguishable. I have only 
six adults of similis, but eighty-five adults of taschenbergi, and 
it seems to me that every one of the females can be distin- 
