220 
Psyche 
[September 
A PRELIMINARY STUDY OF THE TRACHEAL 
SYSTEM OF THE MATURE LARVA OF 
BLEPHARIPA SCUTELLATA 
R-DESVOIDY. 1 
By Milton F. Crowell. 
Blepharipa scutellata R-Desvoidy is one of the imported 
parasites of the gypsy moth, Porthetria dispar (L). The 
individuals studied emerged from pupae of the moth col- 
lected in July 1929, in southern New Hampshire. I had but 
four larvae and one puparium to examine, hence the study 
of this insect is by no means complete, and note can be made 
of only the more obvious features. 
The larva of this insect has the amphipneustic type of 
respiratory system (Palmen 1877, DeGuyse 1926) charact- 
erized by one pair of functional spiracles on the prothorax 
and from one to three pairs of functional spiracles at the 
end of the body. This is considered to be a secondary, 
physiological type, (DeGuyse 1926), but the larvae of 
muscoid flies possess a higher type in a rudimentary, or 
nascent state. 
The Spiracles. 
The anterior pair of spiracles was not observed in detail. 
Their general position was noted in a study made of the 
tracheae visible through the integument at the cephalic end 
of the body. The main tracheal trunk appeared to bend up- 
ward and join the body wall near the posterior margin of 
the prothorax. Since Snodgrass (1924) found the prothor- 
acic larval spiracles of Rhagoletis pomonella Walsh (the 
apple maggot) to be located in a position similar to these 
iContributions from the Entomological Laboratory of the Bussey 
Institution, Harvard University, No. 321. 
