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Ocean. Down the east and west coasts of Australia spread fishes from the warmer equatorial waters. On the Western Australian coast a mixture of these warm and cold water faunas is met with all the way from Mandurah, some 40 miles south of Perth, right up to Shark Bay, and possibly as far as the North-West Cape itself. The number of species of fish at present recorded for Western Australian waters is about 220, but our knowledge in this respect is still very incomplete. In fact, the systematic study of the occurrence and distribution of fishes in the West has scarcely yet been begun, and the economical aspect of the question has been left mainly to chance as an industry which would develop of itself somehow, like the industry of gold-digging. The Department of Fisheries has this year been completely reorganized, with a view of systematic development of the State's fish resources. As an index of what may be learnt by further research in Western Australia it is significant to compare the proportion of "table fishes" to the total number of species catalogued. The British seas have 208 species, of which forty only rank as edible; New Zealand has 243 species and thirty-three edible; Tasmania, 207, of which one-third is really edible, but only twenty-one ordinarily sold in the markets; while Western Australia has already some forty marketable species out of the 220 now known. During a Government-conducted trawling expedition from Fremantle to Shark Bay, about five years ago, the trawl was cast 100 times, and on an average three out of every four casts brought up a species new to the coast; and ten of these were new to Science both in species and genera. The fresh-water fishes of the State, owing to the absence of large rivers, can never be important economically; but the sea-fishes which visit the coasts in search of a favourite food have their distribution governed by the warm or cold water currents bearing that food. Swarms of medusæ, mollusca, and larval crustacea crowd along the coast according to season and attract shoals of small fishes, which in turn are pursued by enemies usually inhabiting waters elsewhere. The study of the ocean temperatures which regulate the lower forms of life on which the fishes feed has as yet not even been attempted as far as Westralian seas are concerned, though the data could easily be obtained from the engine-room records of the trading steamers. That a big fishing industry is possible and will yet be developed along the Western Australian coast is certain, and must attain to great export dimensions. Even such countries as Italy and Spain draw over one and a half millions sterling every year from their "Harvest of the Sea." The total "catch" of Western Australia each year is about 1,500 tons, worth about £52,000, while nearly an equal sum of money is spent on importing cured fish from abroad.

Space does not admit of any extended discussion of the minor marine organisms of the Westralian seas. There is nothing distinctively Australian about them, except those along the south coast. Northward the characteristic forms of the tropical waters occur. The pearling industry (which begins at Shark Bay and extends to the extreme north coast) produces about 1,000 tons of pearl-shell (worth over £150,000) and about £50,000 worth of pearls annually. Good sponges occur freely at all points where the sea bottom is composed of the crystalline rocks, but, so far, have been neglected.

Insects with a world-wide range are rare in Australia, but the insect fauna of the continent is a particularly large one. It is enormously rich in beetles, flies, wasps, bugs, and, to a slightly lesser extent, in butterflies and moths. The peculiar characteristics of the Australian insects are so marked that it is claimed an expert in such matters would at once recognize any specimen as from Australia. From New South Wales northward there is, as was to be expected, an increasing analogy with the insect fauna of the Malayan Archipelago and Southern India, and even a slight admixture of species. From New South Wales to Tasmania the insect fauna has its nearest affinities with that of New Zealand and Western Polynesia. In the open sandy plains of the interior of Australia, and extending to the heath and tangled scrubs of the West, the affinities are strongest with the insect fauna of South Africa, but the differences are all strongly marked.

It is estimated that a full catalogue of Western Australian insects would run to quite 30,000 species, but only the barest fringe of this great field of work has yet been entered. The three distant relationships of the Australian to other insect faunas, and its own peculiarly distinctive character, attest the long-continued isolation to which it has been subjected and the extremely early period of its origin. The development of this fauna has, however, proceeded under the same forces as those pertaining to other parts of the world; hence all the familiar forms of northern hemisphere insect life and its province in the economy of Nature have "representative forms" in Australia. Thus there are dragon-flies by the sides of streams; there are wasps, hornets, bees (all small and no larger than the common house-fly), mosquitoes, flies, fleas, cockroaches, spiders, etc., all fulfilling their natural work and appearing almost identical with the northern familiar forms. That the competition for existence between the different forms of insect life had long ago reached a normal level or balance in Australia is also attested by the general