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ZOOLOGY.

LIFE AT THE SEA-SIDE.

"Come unto these yellow sands."

A GLANCE at a map of the British islands will show that they are indented with numerous bays, lochs, or firths, differing greatly in size and form. Nor do they differ less in the degree to which they are exposed to ocean storms and currents, the temperature and depth of their waters, the proportion of fresh and sea water that they contain, and in the geological structure of the sea-bottom, and of the adjacent shores. All these circumstances exert an influence on both animal and vegetable life. Changes in the marine vegetation are attended with changes in the species of animals that depend on that vegetation for support. And the fact of a sea-bottom being sandy or gravelly, oozy or rocky, renders it fit or unfit for the residence of whole tribes of creatures that live on others more minute, and are in turn preyed on by species more powerful than themselves.

To know with accuracy the various kinds of animals found as permanent residents or occasional visitants in any one of those bays, would demand the careful and untiring observations of many years, and would require an amount of knowledge that comparatively few possess, and an expenditure of time that not many mortals in this "work-day world" have at their disposal. But to note the species that are most common, with the times of their appearance when they are not permanently present, and the circumstances under which they live, is not difficult; and this all might do to a greater or less extent. Such labour would be highly instructive and interesting. It would train the mind to habits of accurate observation, patient research, comparison, and generalization. It would be an efficient promoter of bodily

health, by giving an inducement to active exercise out of doors; requiring the use of the gun and the net, the spade and the fishing-line, the dredge and the towing-net; and at the same time habituating the observer to habits of hardy endurance and of self-reliance.1

Before bringing under the notice of the reader some of the most common animals to be met with at the sea-side, it may be well to mention that all animals have been arranged in four great groups or sub-kingdoms. These divisions are founded not on external form only, but on internal structure, and especially on well-marked modifications of the nervous system. These groups

are

1st, VERTEBRATA-Animals having a skull and back-bone or vertebral column, such as man and quadrupeds, birds, reptiles, and fishes.

Next follow those which are destitute of the skull and backbone, and from this circumstance are termed INVERTEBRATE. They consist of—

2d, MOLLUSCA-Soft-bodied animals, such as the cuttle-fish, the snail, and the oyster.

3d, ARTICULATA-Jointed animals, such as spiders, insects, crabs, and

worms.

4th, RADIATA-Rayed animals, such as star-fishes, sea-jellies, and zoophytes.

In the brief notice which can here be given of any of these animals, I shall begin with birds. I do so, because of the beauty of their forms, the variety of their plumage, the grace of their movements, and the animation they impart to both inland and maritime scenery. Instead of marshalling these according to their families and orders, let me introduce them in a more general way, by means of an address delivered at Holywood to an audience consisting of boys and girls.

2 Those records of animal life possess a great interest for the zoologist. They have a twofold value: they enable the man of science to compare the list of one locality with that of another, and thus supply material for tracing the laws that regulate the diffusion of animal life; and next they place in the hands of the inhabitants of that district the means of observing what changes have taken place in the species of animals which it contained. Such changes are more frequent and more numerous than those who have not attended to the subject would probably suppose.

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