TWENTY-FIFTH ANNUAL REPORT 137 
to the exhibition tanks to avoid losses. All fishes left in the well 
of the boat while the vessel is moored behind the Aquarium die 
within two or three days. The low salinity of the harbor water, 
less than half that of the open sea, is shown in the following 
table: 
RECORD OF MONTHLY MEAN TEMPERATURES AND SPECIFIC 
GRAVITIES OF THE WATER OF NEW YORK HARBOR AT 
THE BATTERY, DURING THE YEAR 1920* 
Temperature. Specific Gravity. 
AMUAG Vee k = ttc a ae 39° 1.014 
Nebruanry s4 Wake ae Ba 30° 1.015 
VID CING 3 eee Chey ie hee 38° Oma 
ATOR spe sas ct) CN a A AZ? 1.007 
Mayo mens See S Lee a: Age Oat 
AUTO pete hte ere es ent 58° 1.012 
“UGK giage a einen eave ects oy ot pb 65° 1.012 
JEN DIOS(0 KS Ghee cesar: ea as 68° 1.013 
September, <2 5 sass Sleek 69° 1.013 
October 3.4... Sk ee 63° IOUS 
November sic.o5 2 .-5s aces 56° 1.013 
Wecembern a... eee 49° 1.010 
The Supply of Fresh Water.—The following table of water 
temperatures, which has been prepared from daily records made 
at the Aquarium, is published with a view to convenient refer- 
ence. The water supply of the City was increased and improved 
in 1917 by the addition of water from the Catskill Mountains. 
An examination of the table indicates that the water flowing 
into the Aquarium since that time has a temperature somewhat 
lower in summer and higher in winter than was formerly the 
case. The greater equability is probably due to the fact that the 
temperature of the naturally cooler mountain water is modified 
by flowing a much greater distance underground. For the pur- 
poses of the Aquarium the greater equability is desirable. 
*From daily observations made at the New York Aquarium by Mr. 
W. I. DeNyse. Specific gravity observations were made with the samples 
of water brought to a temperature of 60° Fahr. 
