SiGERsoN — On the Study of Nerve- Action. 265 



called ' fur on the tongue ' is merely the result of a considerable de- 

 squamation of the epithelial pavement cells which characterise the 

 mucous membrane of that region." 



A different view, however, has been proposed by Mr. Bultin, 

 P. R. C. S., in a paper recently read before the Royal Society of Lon- 

 don,^ — the object of his essay being, as he states it, "to show that 

 schizomycetes form the essential constituent of the fur, and to show 

 as far as possible some of the laws which govern the formation of the 

 fur." His theory may be thus summarised : " The tongue," he says, 

 " is kept clean by free movement, and by being rubbed against the 

 interior of the mouth, gums, and teeth ; but fur almost always exists 

 on the surface both in health and in disease. The fur is generally 

 thickest in the morning before food is taken, and during illness, when 

 the necessary cleansing is not properly performed." Observed under 

 a microscope the scrapings of a furred tongue show : " 1°. debris of 

 food, and bubbles of mucus, and saliva ; 2°. epithelium ; 3°. masses 

 which appear at iirst to consist of granular matter, but which are the 

 gloea of certain forms of schizomycetes." These gloea, he observes, 

 are so closely attached to the hair-like processes that these come away 

 with them, and where they are found " the filiform papillae, instead 

 of exhibiting fine, clear, tapering processes, terminate in processes 

 which are uneven, tuberculated or beaded, and blunted at the ends." 

 This alteration in appearance he considers to be "owing to the pre- 

 sence of these bodies." 



With reference to these statements, it may be replied : 1°. that it 

 has not been demonstrated that the deformation of the epithelial pro- 

 cesses is not due to pathological alteration, rather than to parasitic 

 growth. Such an alteration would be represented by what my dis- 

 tinguished master. Professor Ranvier, has termed ' ' la tumefaction 

 trouble des cellules." This turbid cell-tumefaction takes place under 

 like conditions. Whenever a slight irritation exists, or an abnormal 

 variation of the nutritive fluid occurs in the epithelial tissues, "the 

 epithelial cells swell and become filled with an albuminous fluid, con- 

 taining flne granulations." This, in my opinion, would be the imme- 

 diate cause of the alterations of the epithelial cells in case of furred 

 tongue. On a mucous surface, so altered, it is quite conceivable that 

 parasitic growth should soon form, because the "vital" resistant 

 power of the tissue must be considerably lessened. It may be added, 

 that if the formation of fur were due, essentially, to the proliferation 

 of parasites, it would be very difficult to understand its occasionally 

 rapid disappearance, either without remedies, or on the exhibition of 

 medicines which are not known to be parasiticidal, and are not applied 

 to the tongue. It would be impossible to account for the cleaning of 

 one haK the tongue, whilst the other half remained loaded, in the 

 case quoted, if we take the view of Mr. Bultin as correct. 



'^ " On the Nature of Fur on the Tongue," by Henry Tventham Bultin, 

 F.E.C.S. — Froceediiigs of the Royal Society, Iso. 195, 1879. 



