COVER-SLIPS AND SECTIONS. 279 



tended. Through the work of these investigators we now 

 know that the pathogenic properties of staphylococcus 

 pyogenes aureus are due to a definite soluble toxin elab- 

 orated by it : that this poison is produced under arti- 

 ficial Conditions of cultivation, and may be separated 

 from the living organisms by filtration ; that when 

 injected into the living animal body its effects upon the 

 tissues are essentially reproductions of those accompany- 

 ing the growth of the organism itself; that when this 

 action is tested upon particular cells, such as erythro- 

 cytes and leucocytes, two distinct properties are exhib- 

 ited, one a hamolytic, through which the red corpuscles 

 of the blood are dissolved, the other a leucocidic, through 

 which the white blood-corpuscles are destroyed ; that 

 the hsemolytic and leucocidic properties are distinct 

 from one another, and are due to the activities of two 

 lysins, of which the staphylotoxin is (in part?) com- 

 posed, and which may be separated from one another by 

 appropriate methods of analysis ; that the result of the 

 treatment of animals with gradually increasing non-fatal 

 doses of staphylotoxin is the appearance in the blood of 

 the animals of antitoxic bodies (antilysins) that inhibit 

 the action of the toxins (lysins) ; and, finally, that in 

 the serum of certain animals (man and horse) similar 

 antilysins in varying amounts are normally present. 1 



Petersen, Paltchikowsky, Proscher, and others have 

 recently attempted to prepare an antistaphylococcus 

 serum. The serum of patients recovering from severe 

 staphylococcus infections contains protective substances 



1 See van de Veld e: Annales de 1'Institut Pasteur, tome x. p. 580. 

 Krauss : Wiener klin. Wochenschrift, 1900, No. 3. Von Lingelsheim : 

 Etiologie uud Therapie der Staphylokoken Infektion (monograph), 

 Berlin- Wien, 1900. Neisser and Wechsberg: Zeitschrift fur Hygiene 

 und Infektionskraukheiten, 1901, Bd. xxxvi. 8. 299. 



