34 SECRETING STRUCTURES. 



according to Dr. Martin Barry's researches, results from the 

 solution of certain cells of a brood, and affords nourishment to 

 their survivors. It is one of other instances in which cells do 

 not derive their nourishment from the blood, but from parts in 

 their neighbourhood which have undergone solution ; and it 

 involves a principle which serves to explain many processes in 

 health and disease, some of which have been referred to in other 

 parts of this work. 



I conclude, therefore, from the observations which I have 

 made 1st, That all the true secretions are formed or selected by 

 a vital action of the nucleated cell, and that they are first con- 

 tained in the cavity of that cell ; 2d, That growth and secretion 

 are identical the same vital process, under different circum- 

 stances.* 



J. G. 



* In Mr. Bowman's elaborate Paper " On the /Structure and Use of the Malphigian Bodies 

 of the Kidney" read in the Royal Society of London, 17th Feb. 1842, and in his Article 

 " Mucous Membrane" in the Cyclopedia of Anatomy, written in Dec. 1841, certain parts 

 of the theory of secretion are well elucidated by a reference to human structure. In my own 

 Memoir, read in the Royal Society of Edinburgh, 30th March, 1842, I endeavoured, by an 

 appeal to facts hi comparative anatomy, to establish secretion as a function of the nucleated 

 cell, and to shew that glandular phenomena are only the changes which the cellular elements 

 of these organs undergo. Mr. Bowman's own observation on the secretion of fat by the 

 cells of the human liver in a state of disease, was an important and positive result ; and 

 Professor John Reid, with whom I had frequent conversations on the subject of secretion, 

 and to whom I had communicated my views on the subject, a year before the publication 

 of my Paper, was in the habit of supporting Purkinje and Schwann's hypothesis, by an 

 appeal to the structure of Mollmcum contagiosum, as described by Professor Henderson and 

 Dr. Paterson in the Edinburgh Medical and Surgical Journal, 1841. 



