1953] 
Nutting — Biology of Euphasiopteryx 
73 
haemocoele. The fourth larva (fig. 5) had recently become 
fixed to the pleural membrane on the left side of the fifth 
abdominal segment. This evidence suggests that the larvae 
are strongly attracted to the host’s abdominal haemocoele, 
and that they probably do not often miss this goal. It is 
possible that entry may occasionally be effected via vul- 
nerable areas of the appendages in contact with the ground. 
In any case, the paired sets of hooks on the second segment 
(fig. 3) undoubtedly assist the larvae during penetration 
of the host. 
There was no apparent evidence of larval entrance on 
any of the 13 parasitized cone-heads, although it might 
be mentioned that five bore from one to four 0.5 to 1.5 mm 
scars on either or both faces of their hind femora. No such 
scars were found on the uninfected specimens. They may 
be significant, but it would be difficult to understand how or 
why the larvae would enter at such a point. It is more likely 
that these scars were earned during battle with other males, 
or perhaps during or after mating. 
Although not exactly popular knowledge, the unusual 
respiratory funnels used by tachinid larvae for obtaining an 
atmospheric oxygen supply have long been known from 
the early biological researches of Nielsen (1909) and Pantel 
(1910). Baer (1920) , Thompson (1928), and Beard (1942), 
have also contributed to our understanding of larval 
respiration and host relationships within this group of flies. 
(See Clausen (1940) for a comprehensive review.) York 
and Prescott (1952) have reported that similar funnels are 
also formed by nemestrinid larvae in grasshopper hosts. 
Euphadopteryx behaves typically for, after the active larva 
enters the cone-head’s abdomen, it perforates the host’s 
body wall and settles down with its posterior spiracles in 
contact with the outside air until it is nearly ready to 
pupate. Perforation of the host integument may be accom- 
plished by means of the minute circumstigmatal spines as 
suggested by Beard, or in the case of larvae such as these, 
perhaps by means of the postcephalic recurved hooks. In any 
event, the larva, with its spiracles in this hole, obstructs 
the normal healing of the wound in such a manner as to 
cause an inward growth of host integument which eventually 
