314 THE ADRENAL, GENERAL MOTOR, AND VAGAL SYSTEMS. 



nasal "mucus" killed anthrax bacilli, that Klebs-Loeffler ba- 

 cilli were almost as actively destroyed by it, and that the viru- 

 lence of staphylococci and streptococci was reduced. Nasal 

 "mucus," however, is largely made up of serum: a feature 

 which also applies to the secretion of the glands of Lieberkiihn. 



Brunner's glands, which occur in the duodenum, at the 

 portal of the intestinal canal, would seem to suggest, by their 

 situation and their general conformation, just such a function. 

 While they resemble in general structure the pyloric glands, 

 to which most authors compare them, they also present many 

 characteristics of the mammary lobules, especially in the man- 

 ner in which their interlobular ducts are disposed. The gland 

 proper is situated beneath the smaller crypts just described, 

 i.e., in the submucous tissues, its ducts penetrating to the 

 surface between the villi or into the crypts of Lieberkiihn: an 

 indication that there is considerable analogy between their 

 products. Indeed, their secretion is also serous: i.e., blood- 

 plasma relieved of its fibrin, globulins, etc. 



The secretion of these two glands is termed "intestinal 

 juice," or "succus entericus," and is regarded by many as 

 capable of acting on starch, proteids, fats, etc., in connection 

 with intestinal digestion: all properties which might not con- 

 trovert any antiseptic power it might possess through the pres- 

 ence of oxidizing substance and alexins. Professor Foster, 

 however, referring to this supposed action on foods, says: 

 "Even at its best its actions are slow and feeble. Moreover, 

 many observers have obtained negative results; so that the 

 various statements are conflicting." And he adds: "We may, 

 therefore, conclude that at present, at all events, we have no 

 satisfactory reasons for supposing that the actual digestion of 

 food in the intestine is, to any great extent, aided by such a 

 juice." 



These two glands are the only ones forming part of the 

 intestinal tissues per se to which the protective functions re- 

 ferred to could be ascribed. Hence, the facts that they both 

 produce a secretion so nearly identical to blood-plasma as to 

 be called "serous," for the glands of Lieberkiihn are the 

 source of serous diarrhoea, and the rice-water discharges of 

 Asiatic cholera, a disease which, as we will show, is the most 



