DEVELOPMENT OF THE HORSE. 9 



delay, and not waiting to give it suck, has then started off at a 

 brisk trot after the nock, with the lamb, scarcely a minute in the 

 world, running freely at her side." x One of the most renowned 

 Arabian mares was apparently equally precocious. In Gleanings 

 from the Desert of Arabia 2 occurs the following passage : — 

 " During a short interval of rest, when on a long and rapid 

 journey — her master being pursued — a mare gave birth to a filly 

 foal. He abandoned the foal, and pursued his course on his 

 mare, the dam ; when he again halted, he was surprised to find 

 the foal shortly make her appearance." This foal was placed in 

 charge of an old woman, and was afterwards known as the 

 Keheilet Ajuz, i.e., the mare of the old woman. I have else- 

 where 3 mentioned that my zebra hybrid " Komulus " was within 

 a minute after birth " rushing about as if he were a young zebra 

 whose existence depended on his at once joining the troop of 

 which his dam was a member." Even the young hippopotamus 

 is said to be most energetic. On one occasion it is stated a hip- 

 popotamus calf, only just born, escaped from its pursuers, and at 

 once made the best of its way to the river. 



Are sheep and antelopes and horses throughout their embryonic 

 life nourished in the same way as the young opossum, or is some 

 more effective plan adopted during at least part of the develop- 

 mental process ? I shall now proceed to show that, while at the' 

 outset the horse embryo has the same simple apparatus as the 

 opossum, a stage is soon reached when more elaborate and more 

 permanent nutritive appliances are provided. Further, I shall 

 point out that when the new apparatus is being substituted for 

 the old, — when the opossum plan is coming to an end, and the 

 more permanent appliances are barely in working order, — that at 

 this critical period the horse embryo may readily drag its anchors 

 and escape — behave as if it were a young American opossum 

 or an Australian kangaroo. 



I shall best accomplish this by describing shortly, and in as 

 simple terms as I can command, the foetal appendages of my five 

 youngest horse embryos. 4 



1 The Naturalist in La Plata. 2 Upton. 3 Veterinarian, November 1896. 



i Since the above was written, I have succeeded in getting a three-weeks' 

 embryo; but for the purposes of this paper, a four- weeks' one is sufficiently 

 young. 



B 



