Cryptotermes havilandi (Sjöst.) is an important pest of domestic timber in West Africa, and in 1957 a study of certain aspects of its biology was made at Port Harcourt, Nigeria.

The alate is positively phototactic on emergence, and the main flights occur at dusk, between 1800 and 1900 hr. Heavy flights continue until 2200 hr., but few alates can be seen after 0100 or before 1600 hr. There is a peak of activity in the drier months of January and February, but flights take place in every month. Emergence for flight is associated with drier atmospheric conditions.

After a change to negative phototaxis, followed by shedding of the wings, the dealates search for a nest site. Tandem behaviour does not occur. The dealates cannot bore into sound wood, and a hole or crack is essential for colony foundation. The entrance to the hole is sealed with material carried in the gut of the insect, according to a fixed behaviour pattern. Dealates seeking to enter wood prefer holes between one and a half and three millimetres in diameter, and cannot use those of less than one or more than five millimetres in diameter. Preference by dealates for particular species of wood was not shown conclusively. There was no discrimination against wood containing lethal doses of borax or Celcure (a proprietary mixture consisting essentially of potassium dichromate, copper sulphate and acetic acid or chromium acetate).

The rate of egg-production, the incubation period, and the duration of the first three instars are recorded. At the rate estimated, egg-production by a physogastric queen could maintain populations in excess of 3,000. Neoteinics are readily produced in isolation from all but the first three larval instars. They may lay eggs from 35 days onwards, and in their first year have much greater fecundity than primary queens.

The economic applications of the observations and experiments are discussed, together with some factors affecting testing of timbers against termite attack.