sexually mature. The male conger was first described in 1879 by Hermes,
who obtained a ripe specimen in the Berlin Aquarium. This specimen was
not quite 2-1/2 ft. in length, and of the numerous males which have been
identified at the Plymouth Laboratory, none exceeded this length. The
large numbers of conger above this size caught for the market are all
immature females. Female conger of 5 or 6 ft. in length and weighing
from 30 to 50 lb. are common enough, and occasionally they exceed these
limits. The largest recorded was 8 ft. 3 in. long, and weighed 128 lb.

There is every reason to believe that eels and conger spawn but once in
their lives, and die soon after they have discharged their generative
products. When kept in aquaria, both male and female conger are vigorous
and voracious. The males sooner or later cease to feed, and attain to
the sexually mature condition, emitting ripe milt when handled and
gently squeezed. They live in this condition five or six months, taking
no food and showing gradual wasting and disease of the bodily organs.
The eyes and skin become ulcerated, the sight is entirely lost, and the
bones become soft through loss of lime. The females also after a time
cease to feed, and live in a fasting condition for five or six months,
during which time the ovaries develop and reach great size and weight,
while the bones become soft and the teeth disappear. The female,
however, always dies in confinement before the ova are perfectly ripe
and before they are liberated from the ovarian tissue. The absence of
some necessary condition, perhaps merely of the pressure which exists at
the bottom of the sea, evidently prevents the complete development of
the ovary. The invariable death of the fish in the same almost ripe
condition leads to the conclusion that under normal conditions the fish
dies after the mature ova have been discharged. G. B. Grassi states that
he obtained ripe male eels, and ripe specimens of _Muraena_, another
genus of the family, in the whirlpools of the Strait of Messina. A ripe
female _Muraena_ has also been described at Zanzibar. Gravid female
eels, i.e. specimens with ovaries greatly enlarged, have been
occasionally obtained in fresh water, but there is no doubt that,
normally, sexual maturity is attained only in the sea.

Until recent years nothing was known from direct observation concerning
the reproduction of the common eel or any species of the family. It was
a well-known fac