20 THE PENYCUIK EXPERIMENTS. 



that even in the horse family hybrids may be fertile, and 

 strongly indicates that very careful attempts should be 

 made to induce the new zebra hybrids to breed. 



Turning from the zebra hybrid, the next most important 

 fact to chronicle is that, by taking advantage of the know- 

 ledge gained as to the habits of zebras, there is now in 

 some respects less difficulty and danger in using Matopo 

 for stud pui'poses than there is in using many ordinary 

 stallions. Matopo, it may be mentioned, has been trained 

 without applying any severe measures whatever, and 

 without making him less a wild animal than he was on his 

 arrival. By gentle treatment he has become quite tract- 

 able. Some days ago I observed the stud groom pulling 

 Matopo's tail with the object of bringing him round to 

 drink. This is one side of the shield ; but there is another, 

 for the same groom would be at once attacked, should he 

 interfere when mares are in the vicinity of the zebra. 

 Under such circumstances Matopo is quite regardless of 

 whips or other instruments of a like nature. 



In concluding my remarks on the zebras I may mention 

 that, like Frederic Cuvier in 1807, I had no difficulty in 

 mating the five-year-old zebra mare with the Arab horse 

 Benazrek ; but unfortunately this mare succumbed during 

 the winter. The two-year-old zebi-a filly which I found so 

 docile and attractive also fell a victim to the dreaded para- 

 site Strongyhis. 



In addition to working with zebras I attempted various 

 crosses with donkeys and with an Indian (zebu) bull, but 

 so far I have failed to obtain any results. 



In connection with my investigations bearing on poly- 

 dactylism and on the development of the horse I may 

 mention that I have now in my possession several speci- 

 mens showing extra digits in the horse and a considerable 

 number of horse embryos. Amongst others I have an 

 embryo for each of the weeks from the third to the eighth 

 inclusive. I have already shown* that in a liorse embryo 

 fourteen inches in length the second and fourth digits 

 * Journal of Anatomy and Thysiology, April, 1S94. 



