544 BIOLOGICAL PHYSICS 



in composition, and of use in the many and various 

 activities in which the tongue takes a part. The produc- 

 tion of the large amount of this exudate or excretionary 

 material, which in the natural and healthy condition of the 

 tongue is constantly being formed and thrown off, requires 

 for its accomplishment not only an elaborate and extensive 

 machinery, but the readily available provision of a large 

 amount of raw and convertible or immediately available 

 material. In the tongue, therefore, we find, and more 

 especially within the meshwork of its muscular structure, 

 in its posterior and middle parts, a large amount of ill- 

 defined and amorphous pseudo- or semi-fatty deposit, which 

 could lend itself to the production of just such material as 

 is exuded by the epithelial membrane of the upper surface 

 of the tongue at its normally or naturally " furred part." 

 This assumption, we think, will supply the answer to your 

 second question, viz. the exudation of what ? The pres- 

 ence, in the greater part of the body of the tongue, of a 

 large amount of ill-defined or metamorphic material would 

 seem to indicate that that material is there for the purpose 

 of meeting a vital or nutritional local need, or of supplying 

 a " dumping ground " for the future disposal of a used-up 

 and semi-effete material, or both ; the former of these 

 indications we may regard as negatived by virtue of the 

 completeness of the vascular mechanism of the organ and 

 its perpetual activity in the most vital processes and every- 

 day work of life ; we must, therefore, fall back upon the 

 second indication, that the tongue supplies a " dumping 

 ground " for the future disposal of used-up and semi-effete 

 material ; and in answer to the question the exudation of 

 what! we would claim that this ill-defined and amorphous 

 inter-penetrating matricial element of tongue issue forms 

 the raw material of the exudate composing the substance 

 of what is known as tongue " fur." 



Another link farther in our interrogations and en- 

 quiries will complete the chain we have been endeavouring 

 to forge, and will, we think, enable us to unite into a 

 harmonious system of exudation, or excretion, and circu- 

 latory disposal of katabolic cerebral material, a series of 

 circulatory acts or operations as complete and united in 

 their working as is to be found within the human system. 



