ITS MORPHOLOGICAL ELEMENTS. 11 



portance that the specimen we are examining should be perfectly 

 fresh ; for none s becomes so rapidly changed and so soon com- 

 pletely decomposed as the saliva. A disregard of this fact is the 

 cause of many of the errors which have led to the most remark- 

 able views regarding the saliva. It is thus, probably, for instance, 

 that Wright* has ascribed to this secretion many properties which 

 have either not been at all noticed by other observers, or at all 

 events in^less degree. We may refer, by way of example, to the 

 taste of the saliva, which, according to Wright, is {e sharp, saline, 

 and slightly astringent," a statement which I must agree with 

 Jacubowitschf in totally denying; for, in opposition to Wright's 

 assertion, I have always found the saliva of healthy persons to be 

 tasteless. The injurious action of saliva on vegetable and animal 

 organisms, which has been observed and described by Wright, 

 depends for the most part, as may be shown by positive experi- 

 ments, on the fact of its not being perfectly fresh. 



The morphological elements of the saliva owe their origin to 

 the mucous membrane of the buccal cavity, and in a lesser degree 

 also to that of the salivary ducts; hence, these bodies will be 

 described in the chapter on " Mucus." In examining expecto- 

 rated saliva we sometimes find not only epithelium and mucus- 

 corpuscles, but also fat-globules, and occasionally the remains of 

 food, as/for instance, vegetable cells or beautifully macerated 

 muscular fibre, and still more rarely vibriones, which take their 

 origin in mucus or fragments of food retained for a long time 

 between the teeth, or in hollow carious teeth. 



The presence of mucus-corpuscles in normal saliva or the buccal 

 mucus has been called in question, and it has been asserted that they 

 only occur after some slight irritation of the mucous membrane of 

 the mouth, as, for instance, after smoking tobacco; but I have 

 always been able to detect some of them in the buccal mucus of 

 healthy persons (even of such as are not in the habit of smoking) ; 

 and as they likewise occur in the saliva of animals, as for instance, 

 of dogs and horses (Magendie,J Jacubowitsch), it cannot be 

 doubted that the buccal mucous membrane, even in its perfectly 

 normal state, throws off these mucus-corpuscles with the epithelial 

 plates, the former indeed being nothing more than abortive 

 epithelial cells. 



* On the Physiology and Pathology of the Saliva. Lancet, 1842. 

 f De Saliva, diss. inaug. Dorpati, Liv. 1848, p. 12. 

 I Compt. rend. T. 21, p. 905. 

 Op. cit. p. 16. 



