HEALTHINESS OF HYBRIDS 97 



another which lived some three months and then 

 succumbed. It is only fair to say that the dam of the 

 latter, who was only three years old when the hybrid 

 was born, had been much weakened by attacks of the 

 strongylus worm, and that she was the victim of close 

 inbreeding. Both the zebras and the hybrids which 

 have been under observation at Penycuik show a 

 remarkable capacity for recovering from wounds. 

 Accidental injuries heal with great rapidity. On one 

 occasion the surviving twin was discovered with a 

 flap of skin some five inches long hanging down over 

 the front of the left fetlock. The skin was stitched 

 into its place again, during which operation the little 

 hybrid fought desperately, and cried piteously ; but it 

 soon recovered, the wound healed, and now scarcely 

 a scar remains. There was no lameness and no swell- 

 ing either at the fetlock or above the knee. Some 

 time ago four hybrid colts and three ordinary foals 

 were attacked by that scourge of the stable, the 

 strongylus worm. One of the latter died and another 

 was reduced almost to a skeleton : the hybrids, though 

 obviously aff"ected, suffered much less than the others, 

 and soon recovered. It is further noticeable that the 

 hybrids suffer less from colds and other slight ailments 

 than the mares and horses amongst which they live. 

 Thus it seems that Colonel Lugard's hope has to some 

 extent proved true. Some years ago, when adminis- 

 tering British East Africa, he strongly recommended 

 the breeding of zebra mules from both the horse 

 and the donkey, beHeving that they would prove 

 exceptionally hardy and possibly impervious to the 

 tsetse fly. So far as Professor's Ewart's experi- 

 ments go, the first part of the forecast has proved 

 correct. Unfortunately, the latter half has not been 

 justified. 



The much dreaded tsetse fly, which has interfered 

 so seriously with the colonization of whole tracts of 



7 



