TWENTIETH ANNUAL REPORT 124i 
maintaining small aquaria in their class rooms. The living 
forms supplied are chiefly small invertebrates, obtained from 
the adjacent coast by the Aquarium’s collector. 
When specially requested, a man from the Aquarium assists 
teachers in establishing their aquaria. The subject of natural 
history is made more interesting by the use of aquaria, and 
many teachers avail themselves of the specimens offered. 
Since the year 1903 there have been daily records kept at 
the Aquarium on the temperature and salinity of the water of 
New York Harbor. These records are unique for New York 
City and have been useful not only at the Aquarium but proved 
very valuable to Metropolitan Sewerage Commission during the 
investigations of the past few years. The records have been 
published from time to time in the reports of the Director of the 
Aquarium and are herewith presented for later years. 
Record of monthly mean temperatures and specific gravities 
at the New York Aquarium during the period from 1912 to 
1915, inclusive. 
(From daily observations made by Mr. W. I. DeNyse*.) 
1912 1913 1914 1915 
Temp. Spec. Temp. Spec. Temp. Spec. Temp. Spec. 
Water Gravity Water Gravity Water Gravity Water Gravity 
EWING EG? 2 vereanere eae 38 1.016 44. 1.01] 4 1.016 4.0 1.015 
February ..... : 0.017 43 1.013 37 1.015 39 1.013 
Vian Chie ee eee ee 1.013 49 1.013 38 1.014. 40 1.013 
JANG Over DS oe ae ee eee ee 43 0.010 46 OKO DS * es Mesa A4. 1.014 
May = TOUT ea po eee 50 1.011 52 1.014 
June 1.014 Saeed ne Ny Abeta 58 1.015 58 1.016 
July 1.016 67 1.016 64. 1.015 G4. 1.014 
PACU OUTS te paee eee 68 1.017 70 1.017 69 1.016 69 1.013 
September .. 68 1.017 70 1.017 68 1.016 69 1.014 
October =) eas. 64 1.017 65 1.016 64 1.017 63 1.015 
INOyeun Grae 58 1.014 57 1.014 57 1.017 56 1.015 
December 49 1.013 bl 1.015 46 1.016 42 1.014 
During the year 914 specimens were purchased by the New 
York Zoological Society as follows: 
Four Blue Angelfishes, 15 Black Angelfishes, 5 Rock Hinds, 3 Red Hinds, 
7 Shark Suckers, 2 Filefishes, 25 Spiny Lobsters, 42 Eels, I Sheepshead, 29 Pork- 
fishes, 2 Red Groupers, 3 Spotted Morays, 5 Green Morays, 2 Cowfishes, 9 Gray 
Snappers, 26 Stone Crabs, 2 Jolthead Porgies, 2 Little-head Porgies, 9 Grass 
Porgies, 17 White Grunts, 14 Spot Snappers, 15 Red Hogfishes, 2 Gags, 3 Black 
Groupers, 4 Dog Snappers, 11 Common Triggerfishes, 9 Margates, 5 Pompano, 11 
Chubbs, 7 Bream, 6 Yellowtails, 4 Spadefishes, 5 Jacks, 3 Blue-striped Grunts, 
7 Schoolmasters, 6 Muttonfishes, 1 Nassau Grouper, 11 Squirrelfishes, 1 Doctor- 
fish, I Moray (Lycodontis), 5 Scamp, 6 Red Groupers, 6 Gray Grunts, 2 Sea 
“Density observations were made with samples of water brought to a tem- 
perature of 60 degrees Fahr. 
