Investigations into the resources of spiny lobsters in Ceylon waters were first begun in 1958 and consisted initially of skin-diving surveys of sand-stone and rocky areas at night. The surveys revealed the presence of lobsters in appreciable quantities in these reefs. Experiments were then carried out to decide on the most effective method of capturing them. Lobster traps of different design were placed in the reefs and rocky areas and the most efficient design was selected for use. This design was used thereafter to assess the spiny lobster resources. However, traps proved ineffective on the east coast as the particular species present there did not enter traps. Where traps failed the resources were assessed using skin-divers. These operations revealed the presence of lobsters in large concentrations in particular areas around Ceylon, especially on the south-west, south and west coasts. (De Bruin, 1960 and 1962). This discontinuity in distribution is discussed in greater detail in a previous publication (De Bruin, 1969. The ecology of spiny lobsters, Panulirus spp., of Ceylon waters. Bulletin of the Fisheries Research Station, Ceylon, 20(2), pp. 171-189).