or Solenostoma, one
of the two known kinds of fish in which the female shows a sense of
her position as a mother. The tube-mouth, as you can see at a glance,
is a close relation of our old friend the seahorse, whose disguised
and undisguised forms in Australia and the Mediterranean we have
already observed when dealing with the question of animal
masqueraders. Solenostoma is a native of the Indian Ocean, from
Zanzibar to China. In the male, the lower pair of fins are separate,
as is usual among fish; but in the female, represented in the
accompanying sketch, they are lightly joined at the edge, so as to
form a sort of pouch like a kangaroo's, in which the eggs are
deposited after being laid, and thus carried about in the mother's
safe keeping. No. 5 shows the arrangement of this pouch in detail,
with the eggs inside it. The mother Solenostoma not only takes charge
of the spawn while it is hatching in this receptacle, but also looks
after the young fry, like the father stickleback, till they are of an
age to go off on their own account in quest of adventures. The most
frequent adventure that happens to them on the way is, of course,
being eaten.

[Illustration: NO. 5. POUCH OF TUBE-MOUTH.]

[Illustration: NO. 6. PIPE-FISH.]

The common English pipe-fish is a good example of the other and much
more usual case in which the father alone is actuated by a proper
sense of parental responsibility. The pipe-fish, indeed, might almost
be described as a pure and blameless rate-payer. No. 6 shows you the
outer form of this familiar creature, whom you will recognize at a
glance as still more nearly allied to the sea-horses than even the
tube-mouth. Pipe-fishes are timid and skulking creatures. Like their
horse-headed relations, they lurk for the most part among sea-weed
for protection, and being but poor swimmers, never venture far from
the covering shelter of their native thicket. But the curious part of
them is that in this family the father fish is provided with a pouch
even more perfect than that of the female tube-mouth, and that he
himself, not his mate takes sole charge of the young, incubates them
in his sack, and escorts them about for some time after hatching. The
pouch, which is more fully represented in No. 7, is formed by a loose
fold of skin arising from either side of the creature. In the
illustration this fold is partly withdrawn, so as to show the young
pipe-fish within their safe retreat after hatching out. It