34 PSYCHE [April 
NOTES ON TACHINID PARASITES OF CHRYSOMELIDAE. 
BY FREDERICK KNAB, WASHINGTON, D. C. 
DurtneG the past summer the writer repeatedly visited some clumps of willows 
at the head of Plummer’s Island, Maryland, in order to observe the habits of Calli- 
grapha bigsbyana. On August 16 the following scene between a tachinid fly and a 
Calligrapha was observed among these willows. Upon the upper surface of a willow 
leaf, near its base, a specimen of Calligrapha was found, and in front, facing it, a 
rather small tachinid fly. The beetle was in the attitude of attention, its antennae 
held obliquely forward, while the fly sat facing it, just out of reach. The beetle 
appeared to be on the defensive and both insects remained motionless for several ~ 
minutes. Finally the beetle advanced, and as it did so the fly retired, walking rapidly 
backward and all the time facing the beetle. Soon the fly reached the tip of the leaf 
and as the beetle bore down upon it the fly quickly transferred itself to the nearest 
leaf, whence it continously watched the movements of the beetle. The beetle 
advanced to the tip of the leaf, immediately turned around and started back again. 
As soon as there was room the fly returned to the leaf and followed close behind 
the beetle, at times even touching it. The pair proceeded back over the leaf to 
the stem and down the branch of the willow some nine or ten inches, the beetle 
winding about among the bracts, leaves and twigs, the fly always keeping close, 
either directly behind or directly opposite on the branch. When the beetle turned 
and came back over the same route the fly still followed close behind, the pair finally 
going out upon another leaf and from this to another one that was in contact. From 
this leaf the route again went to the branch and the rapid course then led farther 
into the bush where it was difficult to follow the movements of the pair. Fearful of 
losing the interesting fly I captured it, together with the beetle. The fly’s behavior 
suggested a contemplated attempt at oviposition. However no eggs could be found 
upon the beetle. 
The tachinid was sent to Mr. C. H. T. Townsend for identification. He replied 
that “the species is probably to be referred to Anisia, and is related to Hypostena 
barbata Cogt., which has been bred from an adult beetle of Disomycha xanthomelaena 
collected near Washington, D. C.”. Mr. Townsend further stated that the specimen 
was opened “‘and disclosed uterine maggots of a type different from any that we have 
so far seen.’ It is evident, therefore, that this tachinid deposits living larvae; 
whether upon the beetle itself (as the actions of the fly would indicate) or upon its 
larvae remains to be determined. 
