572 DISEASES OF THE MAMMARY GLANDS. 



forms of mammitis are only of degree, and it is difficult, therefore, to 

 see why they should be divided into two distinct varieties. The differ- 

 ence is in regard to the i^rognosis. 



Similarly in practice it is difficult and sometimes impossible to dis- 

 tinguish between an interstitial and a parenchymatous mammitis, 

 because all the tissues of the gland may be involved at a given 

 moment. The only factor which allows of differentiation is the dis- 

 covery of the point from which infection took place. Finally, it is 

 sometimes so difficult to distinguish between galactogenous and lym- 

 phogenous mammitis that the attempt has had to be abandoned. In 

 gangrenous mammitis of milch ewes, for example, the infective organism 

 is found not only in the sinus and the galactophorous canals, but 

 also in the serosity of the interstitial tissue and of the perimammary 

 cedema. 



Without doubt the causative agent of mammitis may enter the 

 gland by three principal channels — the galactophorous sinus, the lym- 

 phatic plexus (after some injury), and the blood circulation. But from 

 the clinical standpoint it is not at all necessary to identify all the causes 

 in order to establish the classification. 



The symptoms allow of a division only into acute and chronic 

 mammitis. Careful examination of the general condition of the patients 

 will afterwards allow cases of primary mammitis to be distinguished 

 from secondary or symptomatic mammitis such as occurs in tuberculosis. 

 Finally, consideration of the conditions under which a particular case 

 of mammitis has appeared, and study of the symj)toms in detail 

 (peculiarities of the milk, local temperature, hardness of the tissues, 

 cedematous infiltration, etc.) will in most cases indicate whether the 

 mammitis be parenchymatous or interstitial. 



This system really differs little from that adopted by Lucet in his 

 work on Mammitis. 



The classification adopted in the following pages is as follows : — 



f Acute . . 



j Parenchymatous or galactogenous. 

 ' -^ ■ ■ 1 Interstitial or lymphogenous. 



Mammitis 



Secondary or f Haematogenous. 

 symptomatic. I Galactogenous. 

 Simple. 



Parenchymatous. 

 Chronic . . J ^ Interstitial. 



f Parenchymatous. 

 i Interstitial. 



We shall leave on one side everything concerning secondary sj^up- 

 tomatic mammitis, the study of which merges into that of the general 

 diseases from which it arises. 



