10 
Psyche 
[February 
Mr. H. J. Reinhard, entomologist of the Texas Agricultural 
Experiment Station and a specialist in Tachinidse, says in cor- 
respondence with the writer that in Texas T. pennipes is para- 
sitic upon Nezara viridiila and Leptoglossus phyllopus. He adds, 
‘T have observed adults depositing eggs on the adult Harlequin 
Bug {Murgantia histrionica, Hemiptera, Pentatomidse) but have 
never been able to obtain any emergence of the parasite.” 
In Massachusetts this beneficial insect is important as an 
enemy of the squash bug, and in the following pages it is treated 
in its relation to this host. 
Methods employed. 
The following account of the life history and habits of 
Trichopoda pennipes has been taken from field and laboratory 
records compiled b}^ the writer during an investigation of the 
squash bug. Collections of the bugs in the field furnished 
parasitized material for breeding purposes and also indicated 
the percentage of infestation. In the laboratory the parasitized 
bugs were kept in breeding cages containing small potted squash 
plants. The cages used were devised at this Station, and are 
so built as to afford a maximum of light. A vertically-sliding 
pane of glass comprises the door, and, this, together with a 
hinged glass top, allows all corners of the cage to be readily 
observed from the outside. The sides and back of the cage may 
be covered with fine-mesh cloth screening, or with copper wire 
cloth. During this investigation, the cages rested on pieces of 
slate covered with an inch of soil, to provide normal conditions 
for pupation of the parasite. 
LIFE HISTORY. 
The Egg. The female fly la}^s its eggs upon the body wall of 
the host, to which the eggs are firmly attached. The great 
majority of the eggs are found on the sides of the abdomen and 
thorax, although they are sometimes seen fastened to the upper 
surface of the body and the head, and rarely to the antennae and 
legs. 
The length of time necessary for the hatching of the egg 
was found to be in the neighborhood of thirty hours. To prove 
