SEVENTH ANNUAL REPORT. 85 
rearing boxes in which young fish are kept while the yolk-sac 
is being absorbed. All these devices rest upon the broad stone 
coping of the pool, the pool itself being a receptacle for the young 
fish after the absorption of the yolk-sac, when they begin to feed 
freely. 
This hatchery, with its troughs and jars, has a capacity of about 
two million eggs at one time, and is fitted for the hatching of 
both fresh- and salt-water species. Through the co-operation of 
the U. S. Fish Commission it is to be at once supplied with eggs 
of the brook trout and the whitefish, and arrangements have been 
made with the Fish Commission for supplies of eggs of various 
species of fishes in season. It is expected that the hatching of 
some of the most interesting of our native food fishes will be 
carried on here during about 8 months of the year. 
EDUCATIONAL WORK. 
In order to bring the Aquarium into closer relations with the 
educational system of New York the forenoons of Monday and 
Thursday were set aside for the use of teachers from the public 
schools with their classes. The Director proposed to the City 
Superintendent that the biclogy teachers in the schools be sup- 
plied with aquarium jars, and offered the services of a compe- 
tent aquarist to assist in establishing them in the school buildings. 
This proposition was accepted, and several schools have already 
been supplied with small fresh- and salt-water collections. It is 
expected to continue this work, which is very highly appreciated 
by the teachers. The cost of the necessary apparatus and the 
transportation of the collections will be assumed by the Board of 
Education. 
A field collector will be appointed on January Ist in order that 
the Aquarium may have a constant supply of local fresh- and 
salt-water fishes and invertebrates, not only for the purpose of 
improving and varying the collections in the building, but for 
furnishing biological material for the use of natural history 
classes throughout the City. 
The fine collection of balanced aquaria, containing both fresh- 
and salt-water forms of life, has been enlarged, and it is proposed 
to increase this interesting series to the full capacity of the lab- 
oratory room on the second floor. This collection is visited 
weekly by classes from the schools, and furnishes to the pupils 
many valuable object lessons. 
The Aquarium has considerable correspondence, and it has 
