MOLLUSCA.—HEDLEY. 
7 
crustaceans, ostracods, and jelly-fish. These were easily taken in the hand-net. In 
these regions, where ice and water are intermingled, the temperature of the water varies 
very slightly in summer and winter, remaining approximately at freezing point. In 
summer the tendency to heating is neutralised by a solution of some of the ice, and in 
winter the cold is absorbed in the production of a surface layer of ice. This constancy 
of the sea’s temperature is favorable to organic life.” 
This description suggests that marine organisms in the sheltered parts of Common¬ 
wealth Bay may, perhaps, endure alternations of freezing and thawing. This is an 
interesting question of marine bionomics which may engage the attention of future 
Antarctic investigators. 
From this station we are fortunate in having a descending series of substations 
at different depths. 
Station I. 
Commonwealth Bay, Adelie Land. 
Fig. 1. 
Dr. Maclean collected in 1913, from the surface of the Boat Harbour, two living 
Pteropods—• 
Clione antarctica Smith. 
Cliodita caducens Quoy and Gaimard. 
and in 3 fathoms in the Boat Harbour he took—• 
Philobrya wandelensis Lamy. 
Philippiella bagei Hedley. 
Submargarita crebrilirulata Smith. 
Lcevilitorina antarctica Smith. 
From 15-20 fathoms, on a floor of rock and brown algae, Mr. Hunter found 
(January 20th, 1913)— 
Margarella refulgens Smith. 
Submargarita crebrilirulata Smith. 
Neobuccinum eatoni Smith. 
Trophon longstaffi Smith. 
