New Yoke Agricultural Experiment Station. 123 



group number contained only eight places instead of ten as at 

 present. 



Making due allowance for this difference in the basis of classi- 

 fication 15 of the 71 groups from the udder are probably com- 

 parable to those found in cheddar cheese. It. is noteworthy that 

 none of these 15 groups are among those most abundant in the 

 udder and only six of them, Nos. 52, 53, 54, 59, 60 and 63 were 

 among the groups given in Table XI. 



Perhaps the best known of these 1 5 groups are Nos. 40 and 69 

 which are typical organisms of sour milk. It should be stated 

 that neither of these organisms was found in any of the more 

 than TOO samples from the Station cows. On the other hand No. 

 40 was found in five and No. 69 in one of 184 samples taken from 

 another herd. The fact that this large number of samples was 

 taken in a strange barn at a single milking suggests the possi- 

 bility of accidental contamination. Nothing was observed in con- 

 nection with the sampling to suggest contamination nor was it evi- 

 dent from the colony growths aside from the unusual physiological 

 properties of the organisms present. The finding of such acid- 

 producing organisms in the udder is not new, similar observations 

 having been made by von Freudenreich, 21 Gorini, 22 and Harrison. 23 



It should be noted in this connection that it was a common 

 practice, in the herd in which these acid organisms were recov- 

 ered from the udders, to permit the cows to be suckled for varying 

 lengths of time by calves. Esten 24 has pointed out that the mouth 

 of the cow is a habitat of acid organisms and it is possible that the 

 mouth of the calf was the source of these acid organisms recovered 

 in the udder samples. 



A more detailed study of the later history of milk and its prod- 

 ucts must be made before the influence exerted bv the udder flora 



21 v. Freudenreich, Ed. Ueber die Bakterien in Kuheuter und ihre Ver- 

 teilung in den verschiedenen Partien des Melkens. Landw. Jahrb. Schweiz. 

 18:401-427. 1904. Also given in Sur les bacteries de la mamelle de la vache 

 et sur la maniere dont elles sont reparties dans les differentes portions de 

 la traite. Rev. gen. Lait. 3:416-425; 440-448; 462-473. 1904. 



22 Gorini, C. Sui Bacteri dei dotti galattofori delle vaeche. Atti della 

 R. Accademia dei Lincei, Series 5 a Rendiconti, 11: (2nd Seniestre) : 159-165. 

 1902. 



23 Harrison, F. C, and Savage, A. The bacterial content of the normal 

 udder. Rev. gen. Lait 9:121-131. 1912. 



24 Esten, W. M. Bacterium lactis acidi and its sources. Conn. (Storrs) 

 Sta. Bui. 59. 1909. 



