SPECIES MISTAKEN FOR PARASITES OF ALETIA. 115 
moth was not yet formed. The duration of the papa state of the Chalcis 
was found to be from eight to ten days in August. In issuing from the 
Aletia pupa it almost invariably eats a hole 
through the dorsal part of the thorax. 40 
The Devouring Tetrastiches (Tetrasli- 
chus esmrui Riley). 41 — The chrysalides of Aletia, 
formed during the latter part of the season, 
are frequently infested with this little parasite, 
each chrysalis nourishing a Dumber which eat 
their way through the shell in the form of small 
black tlies. This parasite is quite generally 
distributed, and has been bred in Texas, Ala- 
bama, and Georgia. The larvse are pale, elon- 
gate egg-like maggots, and the flies issue all 
through the autumn, during mild winter weather 
and (the later ones) in the spring. There exists 
a possibility that this insect is not a so-called primary parasite of Aletia, 
but that it infests naturally one of the large ichneumon id parasites of the 
Ootton Worm. This supposition is. how ever, contradicted by the fact 
that Aletia pups parasited by thischaloid are alw ays found packed to 
Overflowing w ith the Tetrastiehus, w hereas were the latter simply para- 
sitic upon Pimpla ox Chalcis, thc\ would in all probability be found only 
in the abdomen of the Aletia pupa. 
This parasite has also been bred from the fall broods of the worm only, 
which fact may be due to the 'possibility of its parasitism upon Pimpla 
comjuisitor, or from its being, during the summer months, parasitic upon 
some larva other than the Cotton Worm. 
Y\r.. 4'J. — Chalcm ovata, female 
hair-Hoe showing natural *i/.e 
(Original.) 
SPECIES THAT ARK EASILY MISTAKEN FOR PARASITES OF ALETIA. 
Hexaplasta zi<;za<;'- (Figs. 4:5 and 1 1).— In September, 1879, a num- 
ber of minute parasites were sent us by Professor Comstock, with the 
statement that they had issued from 
chrysalides of Aletia. The species 
was undcscribed, and as we could 
placeitin no known genus, we erected 
the genus Didictyum, and described 
the species as />. ziyzaf/ in the Amer- 
ican Entomologist^ 11F, 52, and also in 
the first edition of this Bulletin, p. 
It. Latei', however, we learned, 
through the com toy of Mr. W. EL 
Patton, of Waterbury, Conn., that 
Didicfyum is synonymous with the 
Oynipid genus Eexaplasta of Foer- 
Fiu. 43. — Hexaplasta zigzag: showing female from ' • ^ ^ 
"bore, and male and female antenna*— natural ster, and published the tact III the 
.size indicated in hair-line. (Alter liilev). . . T , , T . . TTT , WAO . 
American Entomologist, 111, 2\s6 (note 
VI). We also there expressed the belief, based ou careful observation, 
