MATERIAL FOR STUDY. 23 
For Aquaria. Hydroids, hydras, and jelly-fish 
for the most part die off in win- 
ter, but sea-anemones, starfish, 
hermit-crabs, shrimps, and cray- 
fish can all be obtained through- 
out the year. Snails and mussels “ 
are also easily kept at all times, Fi 33,— Eggs of Frog 
as are also tadpoles and frogs. erreeecd 
In the spring the eggs of frogs and toads should be 
placed in aquaria and watched. 
Birds. Winter is the best time to begin the out- 
door study of birds. Familiarity with the birds which 
remain north throughout the winter prevents much of 
the confusion which so annoys the novice when he tries 
to observe the newcomers at the time of the spring 
migration. A study of crows, blue jays, and chicka- 
dees, during cold weather should form a part of the 
work for winter. English sparrows must not be 
despised as objects of study, and their habits, both in 
captivity and out of doors, should be watched. 
