148 Dr. T. A. Chapman on Heterogyna penella. 
instance in having led to such extreme modifications: 
of both the pupa and imago of the female moth and of 
her habits. 
It is difficult to understand how the dispersal of the 
species is effected, and how a new area of its food plants 
gets colonised. ‘The newly hatched larva is an excellent 
wanderer but is too small to cover any distance, and the 
older larva is very sluggish. What I have interpreted as 
a desire of the female larva to hide her cocoon, may be the 
result of some wandering that is instinctive at this period. 
its chief resource for dispersion probably les in the fact 
that it will eat almost anything papilionaceous and even 
other things, and so may manage to exist precariously 
across intermediate country. 
When the young larve hatch they eat up the remains 
of their mother, leaving only a few fibrous shreds and 
some pellets, probably of urates. When emerged the 
moth does not void any ejecta or other fluid as nearly 
all insects do on exclusion, and the necessarily present 
effete material is no doubt represented by these pellets. 
The larvee make their way out of the pupa case by the 
opening left in it, and also by forming some very small 
holes for themselves, but beyond this they make no 
attempt to eat the pupa case itself, which remains nearly 
uninjured. They are at first fairly active little wanderers, 
but are too small to travel any considerable distance ; 
they feed readily, and Mr. W. H. B. Fletcher, to whom I 
sent some, tells me that when in their third skin they 
prepare for hibernation by forming a little cocoon, in size 
and form not unlike that of a Nepticula. 
When we come to the male pupa, which presumably 
has not suffered any of these special adaptive modifica- 
tions, we find that to be the case. There is nothing 
definite to distinguish it from one of Zygwna, except the 
very large antenna case, which overshadows the other 
appendage cases in front, and may be the reason why no 
femur case exists between the maxilla and first leg. It 
is black and shining, with abdominal segments | to 7 all 
free. The maxille are short, the antenna cases cover the 
second legs, the tips of the third legs project. The 
appendage cases extend to the end of the sixth abdominal 
segment. The pupa is deep from back to front about 
the seventh and eighth (third and fourth abdominal) 
segments, has a very marked waist (first abdominal seg- 
