ABSTRACTS 83 



2. Such a committee could study the international codes of nomen- 

 clature adopted by the botanists and zoologists and report such modifi- 

 cations as might be necessary to adapt them to the needs of 

 bacteriologists. 



3. They could recommend a suitable date of departure for bacterial 

 nomenclature. 



4. They could report upon the historical validity of the names that 

 are used for bacterial groups, particularly genera. 



5. They could prepare a list of recognized generic names. 



6. They could seek the active cooperation of societies having the 

 same interests, in this and other countries. 



7. They could prepare resolutions to be presented at the next inter- 

 national botanical congress expressing the wishes of the society. 



8. They could prepare a list of suitable names for the designation 

 of chemical changes brought about by bacteria. 



The Hemolytic Streptococci Found in Milk. Their Significance and their 



Relation to Streptococci of Human Origin. David John Davis. 



The occurrence of epidemics of streptococcus sore throat having 

 some relation to the milk supply has directed the attention of recent, 

 workers to the pathogenic properties of the various streptococci found 

 in milk. 



From supplies of milk obtained under various conditions including 

 both pasteurized and certified milk a collection of strains was isolated 

 and subjected to various tests. They were also compared with a col- 

 lection of human hemolytic streptococci as regards their pathogenicity 

 for animals. 



Especial attention was given to the study of the property of heat- 

 resistance on account of its relation to pasteurization. 



Only those streptococci were selected whose colonies were surrounded 

 by a distinct clear zone of hemolysis on human blood agar plates 

 (Type B, Theobald Smith). 



The feebly hemolytic streptococci (type A) were often noted in the 

 milk but were not collected and studied since the interest in sore throat 

 epidemics has centered about the cocci with a clear wide zone. 



Three hundred and twenty-eight sample specimens of bottled milk 

 were collected from different dairies in the city of Chicago. Excepting 

 45 samples from one dairy which furnished certified milk all the speci- 

 mens were pasteurized ; and with the exception of two dairies (17 samples) 

 the holding process was used. 



The time of the year during which these examinations were made 

 was from October 1914 to March 1915. 



Blood agar (human) was used in plating and the counts were made 

 after incubation at 37°C. at the end of 48 hours. The colonies of 

 hemoljdiic streptococci were carefully noted and counted on the plates 

 and later their identity was confirmed by further tests. 



Eighty-five samples yielded on culture streptococci of the strongly 

 hemolytic variety. The number in different samples varied consider- 



