president's address. 
663 
possible dispersion of their ova through the agency of aquatic 
birds. Of the nuviatile Mollusca Mr. Sanger says that the 
Unios sestivate in the mud; that the gasteropods (five species) die 
when the creeks dry up, but that each flood stocks the creeks again, 
young ones in all stages of growth being met with in the flood 
waters. Some of the land mollusca are remnants which have 
found a haven of refuge of restricted area " on the southern escarp- 
ments of the elevated land or in the deeply shadowed gorges of 
the same," forming single colonies, or if more then widely 
separated. The Crustaceans are either burrowers like Astacopsis 
or Telphusa, or they are Entomostracans which like Apus develop 
only after their eggs have been dried up. The Honey Ants have 
learned to store up honey in a remarkable way, certain workers 
being set apart as receptacles for the honey collected by the 
other workers of the community. 
An elaborate series of observations extending over several 
successive meterological cycles — if such were possible — would 
probably show a considerable corresponding ebb and flow both in 
regard to species and to individuals. In times of unusually pro- 
longed and trying drought, the fauna in spite of the assumption 
of adaptive characters must still suffer severely; and recovery 
only become possible by a succession of very good seasons leading 
to increased fertility on the part of the survivors, or providing 
for the influx and establishment of immigrants. 
Thus the Larapintine region furnishes an Australian phase of 
a state of things analogous to what obtains in arid regions 
in other parts of the world. In keeping with the characteristic 
and paramount claims of humidity, the call is for animals 
pre-eminently endowed with sestivating capabilities. In Central 
Australia in winter the winds are cold, and the nights 
frosty; but allowing for all this it is still a land of sunshine. 
It may even be called a land of perpetual summer by contrast 
with some parts of North America, of which Merriam says that 
the cold in winter is so intense that it is quite a common 
occurrence for trees five or six feet in diameter to be frozen to the 
heart. In so far as hibernation is due to the influence of intense 
s s 
