﻿IN THE LUANGWA VALLEY, NORTHERN RHODESIA. 



237 



During the latter part of August the laboratory was raided during the night 

 by hordes of a red driver-ant. These climbed the bottles in which the tsetse-flies 

 were kept, bit through the gauze, and entering destroyed every fly. The bottles 

 in which the pupae were kept were also entered but the pupae were not damaged. 

 A still active larva also, curiously enough, escaped injury. This incident is not 

 recorded as suggesting that driver-ants are enemies of the flies in nature, but as a 

 record that the larvae and pupae are not destroyed by these insects. 



Table showing the duration of the pupation period of G. morsitans at various 

 temperatures (altitude 2,000 ft.). 



Period during 



which the 



pupae were 



obtained. 



Number of 



apparently 



healthy pupae. 



Number of 



pupae from 



which flies 



emerged. 



Average 



duration of 



the pupatioa 



period 



in days. 



Mean 



temperature 



in laboratory. 



Approximate 

 mean tempera- 

 ture to which 



the pupae 

 were exposed. 



Relative 



humidity 



of the 



outside 



air. 



June 27-30 



3 



3 



51-0 



— 



67° 



48-6 



July 1-15 

 „ 16-31 



6 

 24 



5 

 18 



46-6 

 38-7 



64-1° 

 683° 



70° 

 71° 



V 45-7 



Aug. 1-15 

 „ 16-31 



21 

 5(?) 



9 



1 



35-5 

 33-0 



69-4° 

 73-0° 



73° 

 76° 



1 35-8 



Sept. 1-15 

 „ 16-30 



2 

 14 



2 



12 



25-0 

 24-5 



72-7° 

 80-7° 



82° 

 83° 



I 315* 



Oct. 1-15 

 „ 16-31 



22 



20 



15 



10 



22-9 

 23-3 



82-9° 

 86-4° 



85° 

 85° 



t 31-8* 



Nov. 1-15 

 „ 16-30 



17 

 25 



6 

 16 



24-2 

 25'9 



86-0° 

 81-5° 



83° 

 80° 



) 



y 41 1 

 J 



Dec. 1-15 

 „ 16-31 



27 

 13 



23 

 12 



27-1 

 27-6 



80-6° 



78-8° 



79° 

 78° 



1 69-1 



Jan. 1-15 

 „ 16-31 



20 

 31 



16 

 -28 



27-6 

 29-1 



79-0° 

 78-0° 



78° 

 77° 



1 77-7 



Feb. 1-15 

 „ 16-29 



48 

 40 



32 



30 



31-0 

 30-1 



77-2° 

 76-9° 



77° 

 77° 



1 73-8 



Mar. 1-15 



— 



— 



— 



78-8° 



— 



62-5 



* Approximate. 



