■58 



alexiues contained in the blood itself on the other 

 side carry on their battle for supremac\\ These 

 antitoxins or protective forces have been held — as 

 first definitely advanced by Metchnikoff— to consist 

 in the leucocytes or white corpuscles, on the grounds 

 not only that they appear in increased numbers 

 (leucocytosis) under such conditions, but also that 

 they can be seen to actually take the bacilli into their 

 substance and to destroy them. Hence in this con- 

 nection they have received the name of phagocytes. 

 Latterly however it has been found that the plasma 

 (or strictly fluid portion) of the lymph and blood 

 itself contains some chemical substance or substances 

 which wage no inconsiderable part in the struggle. 

 " The essential and primar}^ element in the resistance 

 " or immunity of tissue or of an animal against the 

 " growth and multiplication of a microbe is the power 

 " of the tissue juices (plasma, serum, or lymph) to 

 " injure or destroy the microbe by virtue of its 

 *' alexiues, that then the so altered microbes may be 

 " easily taken up by leucocytes (attracted there) and 

 " further broken up and removed— phagocytosis." ^' 



Now the septic organisms may be so intensely 

 toxic, or on the other hand the antitoxins of the 

 attacked animal may be so feeble, that fatal results 

 may ensue before the production of any of the secon- 

 dary local lesions. This no doubt is rare : most 

 frequentl}^ we find at any rate some of the effects of 

 the alteration in the characters of the blood. These 

 eff"ects take the form of congestions, and may be seen 

 in the brain and its coverings, in the alimentary canal, 

 and in the solid abdominal viscera, the latter (liver 

 and spleen) often becoming greatly enlarged. The 

 lymph glands are swollen, and their bloodvessels shew 

 the conditions to be presently mentioned in connection 

 with the capillaries generally. The lungs may become 



• Klein. Micro-organisms and Disease. New Edition, 1896, pajfe 570. 



