BOOK VIII. Lxviii. 170-LXIX. 173 



niuch preferred to wild asses at that period ; but 

 after his tirae the ass lost favour as a delicacy. 

 Animals of this genus very quickly flag when their 

 sight begins to go." 



LXIX. A mare coupled with an ass after twelve ^"^: 

 months bears a mule, an animal of exceptional 

 strength for agricultural operations. To breed 

 mules they choose mares not less than four or more 

 than ten years old. Also breeders say that females 

 of either genus refuse stallions of the other one unless 

 as foals they were suckled by females of the same 

 genus as the stallions ; for this reason they stealthily 

 remove the foals in the dark and put them to mares' 

 or she-asses' udders respectively. But a mule is 

 also got by a horse out of an ass, though it is 

 unmanageable, slow and obstinate. Also all the 

 foals from old mares are sluggish. It causes mis- 

 carriage for a mare in foal by a horse to be put 

 to an ass, but not vice versa. It has been obsei*ved 

 that female asses are best coupled six days after they 

 have borne a foal, and that males couple better when 

 tired. It is noticed that a female that does not 

 conceive before she casts what are called her milk- 

 teeth is barren, as is one that does not begin to 

 produce foals from the first coupHng. Male foals 

 of an ass by a hoi'se were in old days called hinnies, 

 while the term mules was used for the foals of a mare 

 by an ass. It has been noticed that the offspring of 

 two different races of animals belong to a third kind 

 and resemble neither parent ; and that such hybrids 

 are not themselves fertile : this is the case with all 

 kinds of animals, and is the reason why mules are 

 barren. A number of cases of reproduction by Cases o/ 

 mules are recorded in our Annals, but these were ^^^utes^ *" 



