Preliminary Experiments on the Annual Cycle of the Red Locust (Nomadacris septemfasciata, Serv.)

Abstract

Egg-pods of the Red Locust (Nomadacris septemfasciata, Serv.) deposited on the 17th January 1933 at Mazabuka, Northern Rhodesia, were kindly sent by air-mail to the Imperial Institute of Entomology by Mr. W. Allan. On their arrival 14 days later, the eggs were found to be perfectly healthy, apart from some having been damaged by pressure. Entire egg-pods, with the surrounding soil, were placed in wet sand in flower-pots and put in a glass cage. The temperature in the cage was kept at 100°F. during the day and 80°F. during the night, but that of the sand was probably somewhat lower. Hoppers began to hatch on the 2nd of March and were kept at the same temperatures, with a humidity as near the saturation point as could be maintained. The first adult appeared on 8th April, and the majority of hoppers became adult by the 18th of April, six and a half weeks after hatching. Owing mainly to cannibalistic habits of the hoppers, only about 40 adults were obtained.It was obviously impossible to plan any serious experiments with such a small number of locusts available, without risking the loss of the entire stock, and it was decided to use them for a preliminary experimental test of the conditions necessary for the sexual maturation. This particular problem is of great practical importance and no data bearing on it were available.