Historical sketch on Immunity 519 



prickles were found to be surrounded by a mass of amoeboid cells 

 such as we see in human exudation as the result of the introduction 

 of a spine or other foreign body. The whole process took place 

 under my eyes in a transparent animal possessing neither blood nor 

 other vessels, nor a nervous system. The first point was settled. 

 The inflammatory exudation must be considered as a reaction against 

 all kinds of lesions, the exudation being a more primitive and more 

 ancient phenomenon in inflammation than are the functions of the 

 nervous system or of the vessels. 



I know quite well that, at the period when I made my researches 

 (1882), pathologists regarded inflammation as the consequence, if not 

 always, at least in the majority of cases, of the penetration of micro- 

 organisms. From this followed the conclusion that the diapedesis 

 and accumulation of white corpuscles in inflammatory diseases must 

 be regarded as modes of defence of the organism against micro- 

 organisms, the leucocytes in this struggle devouring and destroying 

 the parasites. According to this hypothesis the significance of in- 

 flammation at once became simple and clear. With the object of 

 verifying my hypothesis I began to make experiments on the lower 

 animals, so abundant in the Straits of Messina, and to make myself 

 acquainted with the results that had been obtained in general 

 pathology and in pathological histology. A perusal of Ziegler's 

 treatise on Pathological Anatomy made it clear to me that in these 

 branches of medical science there had long been accumulated a great 

 number of observations fitted to facilitate the acceptation of the new 

 hypothesis on inflammation and healing. Numerous and well- 

 established facts on the absorption of extravasated blood, on the 

 fate of the coloured corpuscles in the body, on the presence of 

 micro-organisms inside leucocytes, etc., confirmed me in my view. 



When I had got together certain information and a number of 

 facts in support of my hypothesis I communicated the results to my 

 lamented friend, Kleinenberg, at that time Professor in the University 

 of Messina. Both medical man and zoologist, he was well qualified [543] 

 to offer a judgment upon the matter ; this judgment was favourable. 

 Sometime later I had the great pleasure of meeting the celebrated 

 Professor Virchow at Messina. I imparted to him my ideas and he 

 was kind enough to come with me to examine my preparations of 

 Bipmnaria larvae and other lower animals in which I had set up the 

 phenomena of inflammation without the assistance of nervous or 

 vascular systems. This eminent observer greatly encouraged me to 



