288 ACTION OF TISSUE OF CAPILLARY VESSELS. 



to tlie capillary vessels. In some cases these bio- 

 plasts, as well as tlie fine nerve-fibres connected with 

 them, are almost embedded in the wall of the capil- 

 lary, but oftentimes they are seen to be separated 

 from it by a distinct interval, which varies much in 

 extent, as is well demonstrated in some of my spe- 

 cimens. The bioplasts of the nerve-fibres distributed 

 to the capillaries are represented in Figs. 1, 2, 3, pi. 

 XVI, and in the figures in plates XVIII and XIX. 



4. Elongated a,nd stellate masses of bioplasm which 

 belong to the connective tissue. These vary greatly 

 in number, size, and appearance in difierent tissues. 



29*7. Of tlic action of the tissue of capillary 

 vessels during life. — During life a watery solution of 

 nutrient constituents slowly transudes through, or 

 permeates the passive membranous tissue of the 

 capillaries, which thus acts as a filter. If, however, 

 the capillaries be much distended, the membranous 

 wall is stretched and rendered thinner in a corre- 

 sponding degree, and, in consequence, besides mere 

 watery fluid, serum holding in suspension minute 

 particles of bioplasm, traverses the capillary wall. 

 These minute particles of bioblasm having reached 

 the outside of tlie capillary remain stationary, and 

 absorb the nutrient matter around them and grow, 

 giving rise to important changes which cannot how- 

 ever be considered in this place.* In a fm-ther stage 

 of the same process actual rents or longitudinal 

 fissures are produced, and through these white and 

 red blood corpuscles may pass. Loss of blood, such 

 as may endanger life, may occur in this way. a vast 

 quantity of blood escaping through the pores produced 

 by undue stretching of the minute capillary vessels 

 over an extensive surface, as for example, sometimes 

 takes place fi'om the small intestine. If the tension 

 is relieved the elastic wall of the capillary contracts, 



* See " Disease G-erms ; and on the Treatment of tlie 

 Feverish State." 2n(i edition. 



