466 
EULOPHUS sp. 
Plate. XXVII, fig. 11. 
Reference :—Provisionally determined by Dr. W. H. Ashmead, of the U.S. 
Museum. 
Classification :—Order, HYMENOPTERA. 
Parasitic upon the Lasiocampid-oak-defoliating caterpillar. 
Imago.—Much smaller than above. A minute fly, very 
shining, and dark indigo-green in colour. Wings membranous 
and irridescent. See Pl, XXVII, fig. 11. 
Life-History, etc. 
Both of these parasitic flies were bred out of the Lasio-= 
campid caterpillars described above. 
The larva of the larger one on becoming full-fed quits the 
body of its host before it pupates and prepares a small greyish- 
brown longish oval cocoon, }th inch in length, near the dead 
caterpillar skin and attached to the food plant by some white 
silk strands. In this it changes to the pupal state. The cocoon 
opens by a little lid at one end to let out the fly when it is 
ready to issue. 
In the case of the smaller one the minute larve appear to 
pupate within the insect, and not outside. 
The larve of both these flies pupated during July, and the 
adults issued some time in August, 
It is probable that these parasites assist largely in keeping 
down the lasciocampid larve. 
