32 STREPTOCOCCI IN NATURE 



rophytes and (2) to the distinction, if it exists, between strep- 

 tococci which are able to produce local inflammatory processes 

 leading to suppuration and those which produce highly infective 

 and rapidly spreading diseases, such as erysipelas and strangles. 



In view of the confusion respecting species in this genus, 

 the identity of streptococci isolated from the lesions in the 

 various diseases which have been attributed to streptococci is, 

 at the present time, a matter of some uncertainty. There is 

 also considerable skepticism concerning the primary etiological 

 significance of the streptococci in a number of diseases in which 

 they have, heretofore, been assigned as the cause. Recent in- 

 vestigations, especially those of Lignieres, tend to the conclu- 

 sion that they are often secondary invaders in certain of these 

 diseases. Petruschky has pointed out analogous cases in 

 human infections in showing that streptococci play an impor- 

 tant role as secondary invaders in human diphtheria, scarlatina 

 and tuberculosis. 



In the absence of verified results to prove the non-specific 

 relation of streptococci to the diseases which have with reason- 

 able certaintj' been attributed to the activities of this genus of 

 bacteria, these affections are tentatively included among the 

 specific streptococci maladies. It is very important, especially 

 when the use of antistreptococcic serums are in question, to 

 take into account the apparently large number of forms, or 

 species, commonly included in the general statement of a strep- 

 tococcus disease or infection. In 1897, Van de Velde, in a very 

 exhaustive series of experiments, showed that one strepto- 

 coccus antitoxin will not immunize against another save to a 

 very slight degree. 



REFERENCES. 



1. Klein. Seventeenth Annual Report of the Local Government 

 board. Supplement contai?ii?ig report of Aledicat Officers. London. 

 1887. P256. 



2. KuRTH. Arbeiten a. d. Kaiserlichen Gesimdheitsainte, Bd. VII, 



(i89i),S. 389. 



3. Moore. Bulletin JVo.j.' U. S. Bureau of Animal Industry. 

 Washington, D. C. 1893. p. 9. 



4. Pasqu.^le. Beitrdge zur path. Anal. 11. zur allgenieinen Path- 

 ologie, Bd. XII (1893). S. 433. 



5. Petruschky. Zeitschrift f. Hygiene. Bd. XVII. S. 59. 



6. VON LiNGELSHEiM. Zeitschrift f. Hygiene, Bd. X. 1891, S. 331. 



7. Welch. The Am. four, of the Med. Sciences. Vol. CII. (1891). 

 P- 439- 



