92 The Microscope. 



ABSTRACTS. 



THE CONTEST BETWEEN LIVING ORGANISMS AND 



BACTERIA. 



"DROF. Metschinkoff recently published in the Annales de Vlnsti- 

 -*■ tute Pasteur a very interesting study on the fight which is 

 carried on in living organisms between bacteria and similar beings 

 brought from without and the cells of living oi'ganisms ■ — cells 

 which he calls phagocytes, and are of two orders : the leucocytes, or 

 white blood-corpuscles, and the conjunctive cells, which are similar 

 to the preceding, except that they do not move about, but keep always 

 quiet. This fight MetschinkofP has witnessed for the first time on 

 some daphina, small, fresh-water crustaceans, which are subject 

 to become victims to a ^nonospora, a fungus of inferior order. As 

 soon as a monospora invades a daphina, the leucocytes swarm around 

 it, surround it, and destroy it by a process of intracellular digestion. 

 In eighty per cent, of the cases the leucocytes are successful, and 

 entirely kill the monospora; in twenty per cent, the monospora gets 

 the best of them, and the daphina perishes, being unable to sustain 

 the fight. In all cases of parasitic disease, the result of the organism 

 depends upon the result of this fight, which occurs more or less in all 

 cases, from man downwards. In some rare cases, there is no fight; 

 for instance, in cases of cholera des poules the bacteria multiply and 

 grow freely without any show of fight on the part of the phagocytes 

 of the hen; in the guinea-pig, on the contrary, the phagocytes work 

 in a very energetic manner, and the consequence is, that they gener- 

 ally succeed in destroying the bacteria, and the guinea-pig is saved. 

 In some cases, such as that of charbon, caused by bacillus anthracis, 

 the leucocytes take no part at all in the fight, and it is only the 

 phagocytes of the spleen which do something; but they are not numer- 

 ous enough, and are nearly always defeated. When an attenuated 

 virus of bacillus anthracis is locally injected, on the contrary, the 

 'eucocytes fight well, and it is easy to see within their envelope a 

 number of dead bacilli. 



In order to ascertain whether this fight between parasitic fungi 

 and the phagocytes of the body is a regular circumstance, notwith- 

 standing some exceptions, Professor Metschinkoff has extended his 

 investigations to a great number of parasitic diseases; and he has 

 seen that the fight takes place in erysipelas, in malarial fever, in 

 typhus-fever, and other diseases. In other cases it also takes place, 



