June 15, 1921 
Life-History Studies of Three Jointworm Parasites 421 
HOSTS 
Eupelmus allynii is both a primary and a secondary parasite of the 
jointworm. It apparently will breed as freely as a secondary parasite 
in jointworm cells as upon jointworms themselves under both field and 
cage conditions. It has been found breeding as a secondary parasite 
on Ditropinotus aureoviridis , Homoporus clialcidiphagus , and Eurytoma 
sp. both in cages and in the field. We have reared it in connection 
with other parasites from the following species of Harmolita from field 
collections: iritici t vaginicola, maculata Howard, elymicola , elymivora 
Phillips and Emery, atlantica f albomaculata Ashmead, grandis form gran - 
dis f and from what is thought to be a new species which forms galls in 
Panicum clandestinum T.; also probably from II. occidentalis Phillips and 
Fig. 15.— Eupelmus allynii: A, Legs of female; B, legs of male; greatly enlarged. 
Emery, and H. lies penis Phillips and Emery. In the majority of these 
instances it can not be said positively whether or not it was breeding 
as a primary parasite. It may have been and probably was breeding as 
both a primary and a secondary parasite in each instance. It will prob¬ 
ably breed upon any species of the genus Harmolita. 
EGG 
The egg (PI. 77, E, F; 78, A) of this species is perfectly smooth with¬ 
out any sculpturing whatever and is white in color. The average length 
of four eggs was 0.4109 mm., and the greatest width 0.1578 mm. It is 
ellipsoidal in shape; the chorion is thin and elastic; there is a pedicel 
at the cephalic pole of the egg that is nearly as long as the egg itself and 
a slender flagellum at the opposite pole that is scarcely one-fourth as 
long as the pedicel. The pedicel is usually folded back against the egg 
after oviposition. 
The egg is always deposited external to the host. About 50 per cent 
of the eggs found were fastened to the wall of the Harmolita cell by 
means of a delicate, fibrous, netlike structure which was apparently 
woven from fine wdiite threads (PI. 77, E). When this covering was 
found over the eggs it was usually fastened down rather firmly all around 
