CLASS PISCES,
97
up our rivers, as far as the limits of salt water, and perhaps
even beyond it. It is most wary, and difficult to keep in the
net when enclosed. It jumps over the head-rope, and some-
times makes a grand rush with its companions in a body,
tearing its way out, unless the net is in good order. If one
succeeds in leaping over the head-rope, the whole shoal follows
like a flock of sheep.
Mugil chelo, Cuv. Lesser Grey Mullet.
This is not as common as the last-mentioned species.
Some specimens were, however, taken, in June, 1895, in the
Blackwater Estuary.
Family GASTEROSTEIDAE, Day.
Genus Gasterosteus, Artedi.
Gasterosteus aculeatus, Linn. Three-spined Stickleback.
From its habits and frequency, this is one of the most in-
teresting of the family. It occurs in all situations, in streams,
ponds, and (I had almost written) puddles. It is also to be
found in pools where fresh and salt water are commingled.
I have found this a most variable species, both in size and
armature. In some ponds all the individuals are all similar,
whilst in other ponds or streams various forms occur. I have
never observed which of the named varieties are the most
common. The Three-spined Stickleback is a veritable tyrant
of the water, and appears to fear few enemies, although he is
so small.
Gasterosteus pungitius, Linn. Ten-spined Stickleback.
Tinker.
This is not nearly so common as the last species, being
found more frequently in small streams rather than ponds,
although it occasionally occurs in the latter situations. I
have never found it in brackish water. It is equally pugna-
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