98 THE SEX-COMPLEX 



Effect of reflex in the production of immediate uterine contrac- 

 the uterus! 11 tions, there is no doubt that the high calcium content 



in the blood during lactation, which I have found to 



exist, has a beneficial influence both on lactation and 



on involution. 



Superlactation which is sometimes seen in the poorer 



classes is dealt with in Part II. 



PHYSIOLOGICAL EFFECTS OF MAMMARY EXTRACTS 



Effects of Many observations have been made recently con- 



extracts. ry cerning the action of extracts of the mammary gland, 

 • in the belief that this structure is itself an organ of 

 internal secretion. I have already discussed this 

 question, but it will be worth while briefly to examine 

 the physiological evidence on which the therapeutical 

 use of this extract is based. 



A short review of the work done on these lines up 

 to the year 1913 is to be found in a contribution by 

 Cavagnis 1 . This author arrived at the following 

 experimental conclusions : — At the beginning of preg- 

 nancy the injection of mammary extract augments to a 

 remarkable degree the tonicity of the muscle-fibres of 

 the uterus. This action is less marked on the non- 

 pregnant uterus, and on the uterus towards the end of 

 gestation. 



Further, it has been stated 2 that injections of mam- 

 mary extract produce abortion in pregnant animals. 



The action of mammary extract is, generally speak- 

 ing, hypertonic in regard to all involuntary muscle, and 

 it is said that the mammary extract from a pregnant 

 female has the same action as that from the non- 

 pregnant. If this be so, it is a point of some importance ; 

 but of greater importance is the question whether an 

 extract of the lactating breast gives a more marked 



1 Cavagnis, G., Ann. di Obstet. e Gynecol., 1913, vol. ii, p. 563. 



2 Schiffmann, J., and A. Vystavel, Wien. Klin. Woch., 1913, vol. 

 xxvi, p. 261. 



