SUMMARY 107 



early and fatal, the lymphatic reaction is poorly de- 

 veloped. 



Pathological : — 



(1) The initial lesion of such diseases as sore throat, 

 typhoid fever and appendicitis is a lymphadenitis. 



(2) An increase in the number of the glandular 

 lymphocytes in the subepithelial lymphatic glands 

 accompanies most infections of them. 



(3) The lymphocytes of the blood are formed in part, 

 at least in lymphatic glands. In faucial and intestinal 

 infections these cells are increased in number in the 

 blood. A lymphocytosis accompanies polymorphonu- 

 clear leucocytosis in some pyogenic inflammations, and 

 occurs alone, or predominantly, in Malta fever, measles, 

 variola, infantile gastro-enteritis, some cases of typhoid 

 fever, diphtheria, pertussis, rickets and syphilis. The 

 almost constant presence of lymphocytes about an in- 

 fected area seems to indicate that these cells play an 

 antibacterial part. 



What is the evidence against this hypothesis and 

 what criticisms may fairly be levelled at it ? Perhaps 

 want of direct evidence is the weakest point in the case 

 presented. The following series of experiments would 

 be almost conclusive. The appendix in the rabbit can 

 be detached from the caecum and sutured so that it 

 opens on the skin. A loop of jejunum (devoid of 

 Peyer's patch) can similarly be isolated and made to 

 open at one end on the surface. Various types of 

 pathogenic bacteria could be introduced into these 

 sinuses, and careful observation made as to : — 



(1) Whether a stronger dose could be introduced 

 into the appendicular than into the jejunal sinus with- 

 out harmful effects. 



