290 ACTION 'OF THE BIOPLASM OF CAPILLARY VESSELS. 



drawing, has been previously represented, though it 

 is quite constant and to be demonstrated without 

 difficulty if the mode of preparation I have advocated 

 be resorted to, § 68. 



I beheve that the bioplasts of the capillary vessels 

 play a far more important part in the changes of the 

 body than has been hitherto supposed. They are as 

 intimately concerned in the process of secretion and 

 excretion as they are in the selection, preparation, 

 and distribution of nutrient constituents. The bio- 

 plasts of the capillaries of the lungs are the agents by 

 which certain animal matters are separated from the 

 blood and transferred to the air in the pulmonary 

 air-cells, and it is probable they are also concerned in 

 facihtating the changes which take place between the 

 gaseous constituents of the air and blood. In con- 

 nection with the capillaries of all secreting organs the 

 bioplasts are numerous, and they select and remove 

 certain substances from the blood, and transfer them 

 in an altered form to the secreting cells of the gland. 

 They are in great number upon the vessels of the 

 villi of the small intestines, in some cases being so 

 very close together as to leave little membranous 

 structure between them. These bioplasts of the 

 intestinal capillaries receive the nutrient substances 

 after they have been already once modified by the 

 bioplasm of the epithelial cells of the villi, and 

 transmit it in an altered form to the interior of the 

 capillary, where many of its constituents are at once 

 taken lip by the bioplasts (white blood corpuscles 

 and minute particles of bioplasm)* in the blood 

 itself. 



In many diseases these bioplasts of the capillary 

 walls are much altered, and in cholera I have found 

 that numbers of them have been completely destroyed. 

 The deterioration of the vessels succeeds, and dis- 



* "On the Germinal or Living Matter of the Blood." 

 Trans, of the Microscopical Society, 1863. 



