The object of the present paper is to describe the results of some cage experiments with Zonocerus variegatus, L., carried out at Ibadan between March 1932 and December 1937.The cages used for the breeding experiments were about 2-05 metres in height and were filled with soil to a depth of about 51 cm. The upper part of each cage was made of wire gauze and had a cubic capacity of about 1-43 cubic metres (154 cm. high by 102 cm. by 91 cm.). The grasshoppers were fed on the leaves of sweet cassava (Manihot utiHssima) and water was sprinkled on the food.