280 PHYSIOLOGY AT THE FARM. 



There appears at first sight to be a great difference between 

 the economy of the females of the human race and that of 

 other mammals in respect to the function of the ovaries ; but 

 that difference becomes less striking when the subject is more 

 attentively considered. In the ovary of the females of the 

 human race during reproductive life, at every monthly period 

 an ovule is matured and thrown off, and that uselessly, unless 

 impregnation simultaneously takes place. If impregnation 

 has taken place, then the function of the ovary is suspended 

 till after delivery. But what occurs in common mammals is a 

 close approximation to this course. Tor example, in the cow, 

 soon after the calf is produced, heat arises ; which indicates that 

 a mature ovule is passing from the ovary towards the womb 

 by the Fallopian tube, and if the approach of the male is per- 

 mitted impregnation takes place ; but if the cow is kept apart 

 from the male, the ovule is thrown off uselessly, and the heat 

 after one or two days ceases. In three weeks or a month heat 

 again arises, denoting that another ovule is matured, and has 

 escaped from the ovary ; and so in succession for a number of 

 times, so long as the sexes are kept apart. 



In the males of such animals the heat recurs spontaneously 

 and with force at a certain season, even when they are kept 

 out of sight or hearing of the females; but yet at other 

 seasons the presence of a female in heat is sufficient to throw 

 a male into that state. 



Lactation. Accessory to the organs of reproduction are the 

 glands concerned in lactation. The presence of these glands is 

 the distinguishing mark of the highest order of animals in the 

 animal kingdom. In the female of the human race these glands 

 occupy a place different from their position in the bodies of 

 most mammals ; for in mammals generally the mammae, with 

 the exception of the monkey tribe and the bat tribe, in which, 

 as in the female of the human race, they are situated on the 



