100 Anatomy and Physiology of the Mammary Gland. 



continuously, to a slight degree, during the whole period of lacta- 

 tion ; but it is only in animals that have special reservoirs lor 

 the purpose, that any accumulation of the fluid can take place. 

 In the human female these are so minute as to hold but a trifling 

 quantity of milk ; and the greater part of tlie secretion is 

 actually formed ichile the child is at the breast. The irritation of 

 the nipple produced by the act of suction, and the mental 

 emotion connected with it, concur to produce an increased flow 

 of blood into the gland, which is known to nurses as the draught ; 

 and thus the secretion is for the time greatly augmented. The 

 draught may be produced simply by the emotional state of mind, 

 as by the thought of the cliild when absent, and the irritation of 

 the nipple may alone occasion it; but the two iniluences usually 

 act simultaneously. 



" It is not only in this way that tlie mammary secretion is 

 influenced by the condition of the mind, for it is peculiarly 

 liable to be affected as to quality, by the habitual state of the 

 feelings or even by their temporary excitement. Thus a fretful 

 temper not only lessens the quantity of milk, but makes it thin 

 and serous, and gives it an irritating quality, and the same eflert 

 will be produced by a fit of anger." 



It is well known that cows, which have been used to suckle 

 their calves will, for a time, on their removal, diminish greatly in 

 the quantity of milk. Some never regain it ; that is, tlie mental 

 impression caused by the mere withdrawal of the secretion by a 

 milker is insufficient, in the absence of the young one, to excise 

 the vascular through the nervous S3stem to a full secretion. 

 Many cows also are known to withhold their milk from a new 

 milker. One explanation of this is that after the reservoirs 

 are emptied, over which the animal has no powei', the gland 

 does not continue to secrete its accustomed quantity, the mind 

 of the animal not being reconciled to the altered circumstances 

 in which she is placed. It has likewise l)een stated tliat in 

 some parts of India, retailers of "milk from the cow" peram- 

 bulate the streets driving the animal and carrying a stuffed calf, 

 which they place in the front of the cow each time they serve a 

 customer ; and that unless this expedient is adopted, the animal, 

 having been long accustomed to it, yields but a very insufficient 

 supj)ly. All this goes to prove the influence of the nervous 

 system over lactation, and how necessary it is that attention 

 should be given to the temperament of our dairy cows. 



We may perhaps be permitted to add to these remarks by draw- 

 ing an illusti-ation from another of our domesticated animals. In 

 many high-bred bitches, and spaniels in particular, it frequently 

 happens that an animal having been at heat, but not allowed 

 access to the male, at the end of the period which would other- 



