ScietUific Intelligence. — Zoology. 191 



prodigiously, and great numbers were sent to Mexico. Such at 

 length was the fertiHty of production in St Domingo, that, not- 

 withstanding numerous exportations, herds of 4000 head of 

 cattle were very common in that island, twenty-seven years after 

 its discovery. Some herds are even stated to have numbered 

 8000 ; and, in 1587, the exportation of hides from St Domingo 

 was 35,444 : and, in the same year, 64,350 hides were exported 

 from New Grenada. The principal treatment to ensure fecundity 

 in these animals, was to pasture them in situations where the food 

 possessed saline properties. In places where the quantity of salt, 

 either in the water or plants, was small, they were found to deterio- 

 rate in quality, and to diminish in number. In these climates, 

 the cow undergoes a material change. It no longer furnishes 

 the constant supply of milk which we obtain from it by artificial 

 means in Europe ; and, in order to obtain that fluid at all, it is 

 necessary that the calf should be continually with its mother. 

 The milk obtained for domestic use, is only that which accumu- 

 lates during the night when the calf is in a quiescent state ; when 

 the calf ceases to suck, the milk immediately dries up. The 

 bulls and cows introduced from Eui:ope into South America soon 

 become wild ; and, at the present time, it is only by repeated 

 battues that they are kept in subjection. The ass undergoes, 

 in the provinces which M . Roulin has visited, less change than 

 any other animal. He never becomes wild but in situations where 

 the labour is excessive. The propagation of the species is attend- 

 ed with several instances of deformity. It is very diflerent 

 with the horse. By the independent life which it leads, it al- 

 most resumes the character of the wild horse, and is remarkable 

 for the great similarity of colour. A bright chestnut is the 

 prevailing and nearly the only colour of the horses of South 

 America. The favourite pace of these horses is the amble, which 

 they are taught at a very early age. They do not remain fit 

 for service many years, as they become liable to swellings, 

 which are generally incurable. When, in this state, they are 

 turned out and used for breeding. The result is very extra- 

 ordinary : the colts born from parents which have been taught 

 the ambling pace, have themselves the amble, as naturally as the 

 colts in Europe have the trot. To these colts is given the 

 name of aguilillas. The first importation of dogs into South 



