NATURAL HISTORY
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innumerable moths, two deserve special mention on account of their large size and attractive colouring. One, the magnificent Atlas Moth, has a wing-span of from seven to nine inches, and is one of the largest moths in the world. The other is the Moon Moth, soft silvery green in 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 spectacu- larly 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 during such migrations are sometimes seen after alighting on or falling to the ground. An interesting crustacean not previously known in the Colony is the giant Coco- nut Crab or Robber Crab, two specimens of which were found during 1962. Having a body one foot in length, this huge creature is a relative of the Hermit Crab.
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 particularly 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.