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more likely to make a meal of tsetse thanwc^ versa, whilst the terrestrial 

 tortoises are too scarce to be of any account. Amongst the mammals, 

 certain orders, namely the Insectivora, Chiroptera and Edentata, are 

 obviously of no service on account of their nocturnal habits and the 

 seclusion of their diurnal retreats. Certain rodents, such as hares, 

 may serve the fly for a meal on occasions, but the order can be of but 

 little importance on account of the small size and activity of the 

 majority of its members and the fact that they are largely nocturnal 

 in habit. Of the larger species the porcupine (Hystrix) is entirely 

 nocturnal, but certain squirrels attain a size not greatly inferior to 

 that of a rabbit and are of diurnal habit. The larger forms of the 

 latter family are, however, rarely seen in country suited to the tsetse. 

 No doubt the larger Carnivora are attacked by tsetse when they enter 

 its haunts, but their numbers are relatively so small that they are 

 practically negligible .... The hunting dog (Lycaon) is always 

 migratory, and leopards and jackals, in addition to their scarcity, lie 

 up during the day. The smaller Carnivora FELIDAE, VIVERRIDAE, 

 MUSTELIDAE are also practically nocturnal, and from their alert and 

 active habits are unlikely to submit to be fed upon .... It would 

 seem, therefore, that the whole class of Mammalia, with the exception 

 of ungulates and certain primates, are little fitted to be of service to 

 tsetse even in the aggregate." 



As regards birds, Mr. Jack considers that there is " some ground for 

 belief that for some constitutional cause, such as their conformation, 

 their- armature of feathers, their activity, their habit of pecking at 

 Insects, or such causes combined, birds as a class do not form a very 

 suitable source of sustenance to tsetse." 



Finally, with reference to G. morsitans and the buffalo, Mr. Jack 

 asserts that " it is quite certain that in Southern Rhodesia to-day the 

 fly is not in any way dependent upon this species of animal," seeing 

 that as a rule the two do not occur together in the same districts ; 

 and he remarks in conclusion that " no one having travelled through 

 the fly-belts in Southern Rhodesia .... could entertain the idea 

 that, except in a few localities, the blood of the buffalo is, even at 

 long intervals, a regular food for the tsetse, much less that it is an 

 essential one." 



The defenders of big game commence by insisting that it is by no 

 means proved that the blood of such animals is the sole or even the 

 chief food of Tsetse-flies, as is shown by the conditions in the islands 

 in Lake Victoria, which are excellent breeding grounds for G. palpalis, 

 in spite of the non-occurrence of any large wild animal. The simul- 

 taneous presence of Tsetse-flies and big game in certain areas is stated 

 to be due to the fact that, during the dry season, G. morsitans elects 

 to live and breed in shady, damp places, which at this season of the 

 year are likewise frequented by both big and small game. 



On the ground that from big game Tsetse-flies derive the food 

 necessary for the perpetuation of their species, the extermination of 

 the animals in question in all countries ravaged by Nagana is advocated 

 by some, even to the extent of demanding that all protective enact- 

 ments should be abolished, and that the big game still existing in 

 African colonies and protectorates should be destroyed wholesale. 



Apart from the excessive nature of. such demands, it may be asked 

 what results would be obtained by methods of this kind. If the whole 

 of the game in a given region were destroyed, would stock-raising 

 in countries infested by Tsetse be possible ? We venture to doubt 

 it. The result of such a destruction of life would probably be 



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