11 
Again the posterior end, though usually truncated, has often a conical pro- 
tuberance directed backwards. Smaller papilla-like masses are frequently 
present on other parts of the surface. There is thus a great variety in outline 
and general appearance of the otoliths of the Angler of different ages and even 
of those of approximately the same age. As Immerman has pointed out, it 
would be an interesting problem to determine how variety of life conditions 
cause this variation in the sculpture of otoliths having otherwise essentially 
a constant structure. 
VERTEBRAE AND THE RATE OF GROWTH. 
The vertebrae also show annual rings and can likewise be used to determine 
the age. Taking into consideration the structure and size of the vertebrae at 
the end of the first year one can approximately determine the age by the broad 
and whitish rings laid down in successive-years. In an Angler having a total 
length of 46.5 cm., or about 18 inches, there were four distinct annual rings 
indicating that the fish was four years old. 
In larger specimens it is more difficult to make out the rings, but I have 
estimated the ages as follows: length 46.5 cm. or 31 inches, 9 years; 95 cm. or 
37 inches, 10 years; and 100 cm. or about 40 inches, 12 years. The average 
yearly increment of growth is about 41% inches during the early years, and 
gradually decreases in the older Angler. This is a slower growth than that 
calculated by Fulton (1903, p. 194), who estimates that an Angler four years old 
measures approximately twenty-seven inches. The slower growth could be 
accounted for by the lower temperature in the Bay of Fundy. 
The age-at, which maturity is reached was not determined definitely as a 
sufficient number of specimens of different ages was not obtained. The specimen, 
with a total length of 18 inches, was, however, not yet mature, while all specimens 
over 30 inches in length were mature. 
PIPE RAPTURE: 
Acassiz, A.: On the Young Stages of Osseous Fishes. Proc. Amer. Acad. Sci., 
Vol. XVIII., p. 280, 1882. 
AGAssiz and WHITMAN: The Dev. of Osseous Fishes. Mem. Mus. Comp. 
Zool. Harvard, Vol. X1V., p. 16, 1885. 
Fuiton, T. W.: On the Growth and Maturation of the Ovarian Eggs of Teleo- 
stean Fishes. 16th Annual Rep. Fish. Bd. Scot., Pt. III., p. 88, 1898. 
Futon, T. W.: The Distribution, Growth and Food of the Angler. 21st An. 
Rep. Fishery Board Scot., Pt. I1I., p. 186, 1903. 
Fryp, C.: Die Otolithen der Fische. Diss. Altona, 1901. 
IMMERMANN, F.: Beitrage zur Altersbestimmung der Fische. Wiss. Meeres- 
unters. Arb. d. w. Komm., No. 6. Bd. VIII., 1908. 
Jones, J. M.: Proceedings and Trans. of the N.S. Inst. of Science. Vol. II. 
1871. 
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