114 



reptiles and amphibians. 1 Above all, search should be made for 

 vertebrates if such there be which devote themselves especially to 

 the pursuit of Diptera, since such alone are really of interest from our 

 present point of view. It is true that in Tropical Africa there are 

 plenty of insectivorous animals that may occasionally devour Glossina, 

 but only those belonging to the former category could be protected and 

 bred with advantage. 



As regards birds, a certain amount of evidence was obtained by 

 Prof. Newstead and Dr. J. B. Davey (107) during their investigations 

 in Nyasaland in 1911. "Of the many birds which frequented the 

 tsetse-fly area and its immediate neighbourhood," they write, " post- 

 mortem examinations of 36 different species were made in order to 

 ascertain to what extent, if any, they fed upon Glossina morsitans. 

 Out of the total of 61 birds examined, only two were found to contain 

 the remains of tsetse-flies .... It would seem, therefore, that 

 tsetse-flies do not enter very largely into the dietary of insectivorous 

 birds, but as such birds were everywhere in evidence, they must at 

 least be considered of some potential importance, and may hereafter be 

 found to feed upon tsetse more extensively than these records would 

 lead us to believe. Those which had fed upon Glossina morsitans were 

 the common black drongo of the country, Dicmrus afer, and the small 

 black and yellow throated bee-eater, Melittophagus meridionalis. The 

 other birds which are thought most likely to prey upon tsetses are the 

 crow-shrikes (Prionops and Sigmodus), the grey babbler (Crateropus), 

 and the roller (Coracias caudatus), all the more so seeing that such 

 representatives of the avian fauna were always in evidence throughout 

 the fly-infested areas." 



With regard to Glossina palpalis, Dr. G. D. Hale Carpenter (25), 

 writing after upwards of two years' study of the bionomics of G. 

 palpalis var. fuscipes, on Lake Victoria, Uganda, remarks : " I do not 

 think it likely that Glossina fuscipes is devoured by birds. It may 

 well be that other species such as G. morsitans, frequenting more open 

 country, are devoured by bee-eaters, drongos, &c. But the species 

 which is the subject of this paper, frequenting as it does bush or forest 

 with thick undergrowth, is out of the way of the larger insectivorous 

 birds of powerful flight, which would alone be capable of catching such 

 an active insect." An examination made by Dr. Carpenter " of the 

 stomach contents of 64 insectivorous birds shot while feeding in, or on 



1 Insectivorous fishes need not be considered, since the larvae of Tsetse-flies are 

 terrestrial, but it is of interest to note that at the present time we are acquainted 

 with a number of species of fish that feed upon mosquito larvae. The following, 

 among others, may be mentioned : (1) "Millions" (Lebistes reticulatus, Peters,, 

 otherwise known as Girardinus poeciloides, G. guppyi and Poecilia reliculata), 

 tiny, viviparous fishes, which are very prolific, and occur in fresh and brackish 

 waters in Venezuela, Guiana, Trinidad, and the Windward Islands. They have 

 been exported into various tropical countries for the purpose of reducing the 

 numbers of mosquitos, but in some cases those introduced into Africa are said 

 to have been devoured by frogs. Of three consignments despatched to ^ South 

 Africa, however, one was successful, and has made excellent progress. (2) " Top- 

 Minnows " (Gambusia affinis, Girard), likewise small, viviparous fishes, which 

 inhabit the Mississippi, and fresh and brackish waters from Florida to Texas.. 

 (3) Haplochilus pumilus, Blgr., an oviparous fish occurring in Lakes Tanganyika 

 and Victoria. Although known to devour mosquito larvae, little has been 

 recorded as to the natural history of this species. (4) Haplochilus grahami, Blgr., 

 an active little fish, living in small pools a few yards in extent, in Southern 

 Nigeria. In times of flood, fishes of this species rea'lily migrate from one pool 

 to another. 



