MUCUS. 129 



NATURE OF MUCOUS CORPUSCLES. 



Mr. Addison * conceives " that mucous and pus globules 

 are altered colourless blood-corpuscles," from which opinion 

 it is evident that gentleman believes that the white cor- 

 puscles of the blood pass normally through the walls of the 

 blood- vessels, although he does not appear satisfactorily to 

 have witnessed the exact manner of their escape. 



The perfect identity of organization existing between the 

 colourless corpuscles of the blood and mucous and pus globules, 

 would predispose the mind to adopt that view as sufficient 

 and correct, which endeavoured to prove that they all had 

 a common origin in the blood. 



It must nevertheless be remembered that the notion of the 

 identity in origin of the mucous and pus globule with the 

 colourless blood-corpuscle, rests upon the single supposition 

 that the latter does really escape from the blood-vessels, in 

 which originally it is formed. 



It seems to me, however, that this statement, to which I 

 was myself at one time disposed to attach some importance, 

 may be fairly challenged, seeing that the direct passage of 

 the white corpuscles of the blood appears never to have been 

 clearly witnessed. 



Moreover, the idea of any such escape of the white cor- 

 puscles is opposed to that view which reasoning alone would 

 lead one to entertain ; thus, if the colourless corpuscles of the 

 blood possessed the power of escape from their vessels, no 

 good reason could be advanced why the red globules should 

 not also pass through them. 



If the capillary vessels terminated by open mouths, which 

 we know that they do not in their normal state, then indeed 

 it would be highly probable that mucous and pus corpuscles 

 were the white corpuscles of the blood, escaped from the 

 vessels. 



* Transactions of Prov. Mcd. and Surg. Association, vol. xii. p. 255. 



