312 



SCIENCE. 



[N. S. Vol. XVI. No. 399. 



ity in the application of generic names. The 

 changes incident to the execution of such a 

 reform are few and harmless in comparison 

 with those perpetually necessary where names 

 depend on residues. An excellent example of 

 the workings of the method of elimination is 

 appropriately revealed in the mazes of the 

 recent Mephitis-Chincha-Spilogale discussion. 

 Several prominent zoologists propose to settle 

 this by a new rule* which eliminates elimina- 

 tion and yields definite types for a very small 

 percentage of genera, but which constitutes a 

 significant admission of the essential insta- 

 bility of residues. The new rule leads in the 

 right direction, though it is but a short step 

 on a long journey. 



Obviously, the method of elimination lacks 

 the definite and 'necessarily arbitrary' fea- 

 tures without which, as Dr. Dall well says, 

 ' stability is hopeless.' It may be true that the 

 zoological laws 'are intended to * * * bring 

 about stability,' but it is plain that the inten- 

 tion has not been rendered effective by ade- 

 quate formulation. Systematists who appre- 

 ciate stability may differ on details of the 

 legislation needed to inaugurate the method of 

 types, but they should not use stability as an 

 argument for residues. 



O. F. Cook. 

 - Washington, Aug. 7, 1902. 



SHORTER ARTICLES. 



NATURE OF TPIE SPECIFIC BACTERIAL TOXINS.^ 



After it had been demonstrated beyond any 

 controversy that certain bacteria cause certain 

 diseases, quite naturally the question was 

 asked. How do bacteria cause disease? Sev- 

 eral answers to this question have been ofl^ered. 

 If the liver, spleen or kidney of a guinea-pig 

 which has died from experimental aiathrax 

 be sectioned and examined under the micro- 

 scope, the blood vessels of these organs will 

 be found to be filled with bacilli. In many 

 places the germs have grown so abundantly 

 that they distend the smaller vessels. It was 

 suggested that the anthrax bacillus causes 



* Science, N. S., XVI., 114, July 18, 1902. 



t Abstract of a paper presented by Dr. V. C. 

 Vaughan before the Research Club of the Univer- 

 sity of Michigan. 



disease and death by mechanically interrupting 

 the functions of certain organs. This is 

 known as the mechanical interference theory. 

 It has no support in any other disease than 

 anthrax, and consequently it cannot be ac- 

 cepted as a satisfactory answer to the ques- 

 tion. How do germs cause disease? Another 

 theory offered supposes that the bacteria cause 

 disease by consuming the proteids of the body 

 and thus depriving it of its sustenance. It is 

 known that the proteids are necessary for the 

 building up of cells, and it is also known that 

 microorganisms feed upon proteids. This 

 theory is untenable in the first place because 

 many of the infectious diseases destroy life so 

 quickly that the fatal effects cannot be pre- 

 sumed to be due to the consumption of any 

 very large amount of proteid substance. Sec- 

 ondly, the distribution of the germs in the 

 body is such in many diseases that they do not 

 come in contact with any large percentage of 

 the proteids of the body, and thirdly, the 

 symptoms of the majority of the infectious 

 diseases are not those which would be pro- 

 duced by withdrawing from the various organs 

 their food supply. A third theory supposed 

 that the germs cause the symptoms of the 

 disease and death by depriving the red blood 

 corpuscles of their oxygen. This theory was 

 suggested by the resemblance between the 

 symptoms of anthrax and those of carbon diox- 

 ide poisoning. More extended observation 

 soon demonstrated the fallacy of this theory, 

 especially inasmuch as it was shown that the 

 amount of physiological oxidation going on in 

 the bodies of animals sick with anthrax was 

 not diminished by the disease. In this way 

 the theory that germs destroy life bj' depriv- 

 ing the blood of its oxygen has been shown 

 to be not applicable to anthrax, and in fact 

 not to any known infectious disease. Next it 

 was suggested that bacteria cause disease by 

 forming chemical poisons. This is the theory 

 which has found general acceptance and which 

 is now generally believed to be the true ex- 

 planation, although none of the specific 

 toxins has been isolated in a state of chem- 

 ical purity. The elaboration of chemical 

 poisons by bacteria may occur in either of two 

 ways: In the first place the bacterium, either 



