NATURAL HISTORY
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colour, with a wing-span of from four to six inches and swallow- tailed wings.
Particularly characteristic of Hong Kong in spring and summer are the several species of cicadas, well-known in their brief adult stage for the incessant song of the males. In their immature nymphal stage very little is known about these remarkable insects, which spend years below the surface of the ground. A spectacularly large insect living in ponds is the Giant Water Bug, over three inches in length, which feeds on small fish, frogs and other aquatic creatures. In the summer they fly readily from one piece of water to another, and in the course of such migrations are sometimes seen after alighting on or falling to the ground.
Marine Fauna. The fish of Hong Kong are of extraordinary diversity and hundreds of different species pass through the markets.
Situated just south of the Tropic of Cancer, and flanked to the west by the Pearl River, which brings down enormous quantities of food and nutrients from China, the waters of the Colony support a great variety of both tropical and temperate water fishes, many of which appear seasonally on their breeding or feeding migrations and give rise to major fisheries. In the summer months of recent years large sharks and manta rays have been particularly abundant and have on occasion been the cause of both welcome and un- welcome excitement among fishermen, swimmers and yachtsmen. Infrequent incursions of oceanic water from the south bring with them during the summer such comparative varieties as flying fish and the beautiful but deadly Portuguese Man O' War, with its striking purple and red float and long stinging tentacles.
The invertebrate fauna of the Colony are as diverse in form and colour as the fish. Hidden from sight to all except divers is a profusion of corals, sea-fans, sea-lilies and many other beautiful marine animals.
Flora. It is not possible to make any distinction between the trees of Hong Kong and those of the neighbouring southern parts of Kwangtung Province. The principal trees in the Colony are pine, Chinese banyan and camphor, to which a large number of others have been added since the area came under British administration, the most common being casurina, eucalyptus and Flamboyant. The traditional Chinese belief (fung-shui") that the