24 
. the rest the parasites had not penetrated. The last part of the hosts 
were put aside for rearing the parasites and in the days from the 
10th—15th of July 10 specimens of Meigenia and 16 beetles emerged, 
the larvæ which gave issue to the last named having passed into 
the pupa stage before the parasites had hatched out of the eggs. 
It seemed quite reasonable to suggest that the unnatural conditions 
under which the larvæ had lived during the breeding had influenced 
in some way on the development and caused so many of the hosts 
to escape from being killed by the maggots simply by means of 
moulting; but it is not so; as already mentioned I also saw the 
same in the nature. The reason of this is somewhat difficult so 
to explain and I shall only give suggestions. The embryos of 
Meigenia floralis are at the time of the oviposition at a very little 
advanced stage of development, and the space of time between the 
oviposition and the emergence of the maggot rather long. On the 
other hand the growth of the hosts is very rapid. Therefore it 
is probable, that a great part of the eggs are deposited at so 
critical a moment that the hosts reach their next moult, before 
the maggots are mature to emerge from the eggs. I think that 
this explanation is correct, but I shall only point out the strange 
fact, that not a single of the eggs, deposited on younger hosts 
gave issue to måaggots. 
With respect to the life history of the maggots my investi- 
gations have confirmed those of J. Pantel. 
Åctia pilipennis Fall. 
In the month of July I found on some young pinetrees a 
rather considerable number of branches which were deformed by 
Retinia buoliana. In the larval chambers I found the puparium 
of Actia pilipennis lying close to the dead hosts, and by opening 
some larvæ and pupæ I secured some maggots which were connected 
to the integument of the hosts by means of very strong and con- 
spicuous .funnels. Only a little part of the organs of the hosts 
were consumed by the parasites and the host retains its form after 
