ON THE STRUCTURE OF THE MALl'IGHIAN liODIES 299 



around a diverticulum of the pharyngeal mucous membrane ; its 

 ' follicles ■ precisely resembling the ' alveoli ' of the latter, in being- 

 constituted b}' imperfect septa of rudimentary connective tissue, 

 containing a solid mass of indifferent tissue, traversed by 

 capillaries. 



Can this series of ' vascular glands with false ducts', as they might 

 be called, be extended by any further addition ? I venture to think 

 that it may, and that no one can thoroughly comprehend the structure 

 of the tonsils without perceiving, at once, that there is but a step from 

 them to the liver. A mass of indifferent tissue contained in a vascular 

 plexus and arranged around a diverticulum of mucous membrane, is 

 a definition which would serve as well for the liver as for the tonsil ; 

 it is, further, perfectly in accordance with that theory of the relation 

 of the biliary ducts to the hepatic substance, which is due to Dr. 

 Handfield Jones, and which all recent researches, both anatomical 

 and physiological, tend to confirm, viz., that the liver is essentially a 

 double organ, consisting of two elements, an excretory and a paren- 

 chymatous, different homologically and functionally. It seems odd 

 that, from being a sort of histological and physiological outcasts, the 

 Vascular Glands should turn out, if this view be correct, to be the 

 most important and extensive class of organs in the ■whole body,, 

 claiming the gland /rtr excellence, the liver — as one of their famil}-. 



DESCRIPTION OF PLATE III. [XXV.] 



Figs. I, 2, 3, 4, 5, 6 From the Malpighian body of the Sheep. 



Figs. 7, 8. From that of Man. 



Figs. 9, 10. From the Tonsil of Man. 



The letters have throughout the same signification. 



a. Afferent vessel. 



b. Efferent vessel. 



c. Traversing vessel. 

 c'. Capillaries. 



d. Line of junction between Red Pulp and Malpighian body. 

 d'. Fibrous meshwork. 



t. Red jxilp. 

 /. Malpighian pulp. 

 g. Endoplasts. 

 h. Periplast. 

 /;'. Cell-wall. 



i. Epithelium of the tonsil cavity in the section Fig. 9 ; a vascular papilla is seen 

 extending nearly to its surface. 



