Crossing of North and South African Ostriches. 739 



the majority of their feather sockets had been permanently ruined. 

 Furthermore, they were imported not for their feathers but for cross- 

 ing- with the South African birds, so that their marked qualities of 

 density and strength would have a beneficial effect on the South 

 African birds, the feathers of which were weak in these two respects. 

 It is known that the feathers of the wild birds of the Soudan are of 

 a much higher standard than those of South Africa. Therefore, if 

 the present high standard plumes of the domesticated South African 

 liirds have been evolved by selective breeding from a relatively poorer 

 slock, the introduction of the stronger strain of the Nigerian bird was 

 calculated to give a much better product. 



AccUviatization. — The birds reached South Africa just at the 

 beginning of winter. This was unfortunate, as the sudden change 

 from the heat of the tropics to the severe winter of the midlands of 

 South Africa was a very great strain on their constitutions. Then, 

 also, they suffered severely from wireworm and tapeworm, but by 

 means of continued dosing the trouble was eventually overcome, 

 enabling a start to be made in cross-breeding with South African 

 birds. 



Experiments. — The chief objects of the first experiments were 

 (1) to find out whether the imported birds would breed with the South 

 African birds, (2) whether the progeny would be fertile, and (3) 

 whether the desirable characteristics of the northern bird could be 

 blended with those of the southern. 



The following are the results of these experiments up to the 

 present : — 



(1) The birds interbreed freely. 



(2) The progeny are fertile both inter se and back to either of 

 the original varieties. 



(3) The blending of the desired characteristics has been 

 remarkably successful. The feathers of some of the first crosses 

 can be rated as really first class. This was hardly hoped for 

 even by the most sanguine, as it was con-^idere(l that it would be 

 necessary to cross the birds several times before plumes of this 

 nature could be obtained. The feathers from these cross-bred 

 birds are quite equal in size to the first class South African primes, 

 and the desired characters of density and strength have been 

 introduced to a wonderful degree. The ostriches have been 

 crossed both ways, that is, North African cock with South African 

 hen, and vice versa, and in both cases the above-mentioned high 

 standard of feather has been reached in the progeny. Various 

 other crosses have also been obtained, namely, cross-bred bird 

 mated with either of the original strains, and also two cross- 

 breds mated together. The cross which up to the present has 

 proved most consistently successful has been where the cross- 

 bred bird was mated back to a South African bird. The resulting 

 progeny are three-quarter.s South African and one-quarter North 

 African, and out of twenty-odd birds thus bred at Grootfontein 

 last year every one is coiLsidered first class. A certain number of 

 pure North African ostriches are also being bred at Grootfontein 

 so that the strain may not be lost. 



