NATURAL HISTORY
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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 give rise to major fisheries on their seasonal breeding or feeding migrations. In the summer months during recent years large sharks and manta rays have been particu- larly abundant and have on occasion caused both welcome and unwelcome excitement among fishermen, swimmers and yachtsmen. Infrequent incursions of oceanic water from the south bring with them during the summer such 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 neighbouring southern China. The principal trees in the Colony are pine, Chinese banyan and camphor. A large number of others have been added since the area came under British administration, the most common being casuarina, eucalyptus and Flamboyant. The traditional Chinese belief (fung shui) that the disposition of buildings, graves, trees, water and mountains may affect a person's fortune and destiny, has done much to preserve fine groves of trees, mostly camphor, banyans and clumps of bamboo, around many farms and villages in the New Territories. Some of the mountain slopes, from a distance, seem bare of any plant covering except grass, but on closer observation it can be seen that the water courses are marked by narrow bands of low shrubby growth and scattered trees.
The principal locally-grown fruits include lychee, lung ngan, wong pei, loquat, pomelo, tangerine, banana, papaya, pineapple, custard apple, guava and Chinese varieties of plum and pear. The Portuguese originally introduced the papaya, the pineapple, the custard apple and the guava from South America some time after the foundation of Macau. The tangerine is a native of South China