Rushes and Reeds 343 
Whenever a flower exhibits the liver-like hue we 
see in the spadix, accompanied by an unpleasant 
odour, we may safely conclude that it is seeking to 
attract carrion-loving flies to perform a service for it 
under false pretences. Before it was clearly seen 
how important a part insects play in the fertilisation 
of flowers the relative position of anthers and stigmas 
in Cuckoo-pint would have been considered an 
admirable arrangement to secure fertilisation; but 
when all the circumstances are known this is seen 
to be impossible, and were it not for the visits of 
numbers of a small fly (Psychoda), the Cuckoo-pint 
would cease to produce berries. 
The stigmas ripen and pass maturity before the 
anthers shed their pollen, therefore if fertilisation is 
to be effected at all it must be by pollen brought 
from an older flower. The flies that act as carriers 
of this pollen are very small and moth-like, feeders 
upon decaying fungi and similar delicacies. To 
describe their modus operandi, we will suppose a 
few dozens or hundreds of them have already been in 
the spathe of a Cuckoo-pint that flowered a few days 
earlier than the specimen we are considering. The 
stigmas mature, and the “flower” evolves a most 
unpleasant ammoniacal odour, accompanied by a rise 
in temperature. The Psychode fly to the purple 
spadix, and finding out they have been fooled as to 
its real nature, they follow the scent which leads 
them to the lower regions. The barrier of hairs 
across the entrance easily admits insects going down- 
wards—on the facilis descensus avernt principle— 
though it prevents return. This barrier passed, the 
flies are imprisoned for the present, and can do nothing 
