daphnia breeds at the rate which is almost inconceivable.
"Amateur Fish Culture"
Charles Edward Walker
Thus Snyder and T.B. Robertson found that the rate of heartbeat in the tortoise and in daphnia is reduced to about one-half if the temperature is lowered 10 deg C., and Maxwell, Keith Lucas, and Snyder found the same influence of temperature for the rate with which an impulse travels in the nerve.
"Darwin and Modern Science"
A.C. Seward and Others
In daphnia and Rotifers the facts are different.
"Hormones and Heredity"
J. T. Cunningham