20 ENTOMOLOGICAL NEWS [Jan., ’20 
An Unusual case of Parasitism on Clastoptera 
obtusa Say (Hemip., Cercopidae; Dip., 
Drosophilidae).* 
By W. J. BAERG, Fayetteville, Arkansas. 
In the summer of 1917, during the first two weeks in July, 
when I was collecting the nymphal stages of Clastoptera 
obtusa on alder, Alnus americana, | found the spittle masses 
produced by these nymphs inhabited by small dipterous 
larvae. Many of these larvae I found attached to the nymphs 
of the Clastoptera. Some of them I found lying around 
loose in the spittle masses. As a rule I found but one dip- 
terous maggot to one spittle mass. No maggots were found 
outside of the spittle. 
On taking one 
of the maggots 
and placing it 
near a Clas- 
toptera nymph, 
itwouldimmedi- 
ately proceed to 
attach itself on 
the side of the 
abdomen and 
then bring up its 
caudal end and 
place it on the 
back. .of “the 
a ! nymph.” See 
ogee UGA My Saya Back the accompany- 
“Wty, Gp Wf oe, neon > Ble 
aay //,/ , |) [eae ing text-figure. 
The maggots attach themselves by means of the mandibu- 
lar hooks. As a rule I found but one maggot attached to 
one host, in a few instances I found two maggots attached 
to one nymph. The place of attachment on the spittle 
*From the Entomological Laboratory of Cornell University, Ithaca’ 
New York. 
