On Certain Bacteria from the Air of New York City. 333 



mally foi' B. lactis erythrogenes made me suspect that it might be 

 a variety. Later in the course of the investigation on nitrate 

 reduction on a culture obtained from the air of New York, one of 

 the nitrate tubes showed a growth a little abnormal, the precipi- 

 tate being slightly flocculent, whereas it is usually finely granular. 



B. EKYTHROGEXES EUGATUS. 



B. LACTIS ERYTHROGENES. 



This nitrate culture was one of ten made from an agar plate of 

 the culture No. 10 as described above. A culture on agar gave a 

 flattened, j-ellow growth, covered with coarse wrinkles and entirely 

 unlike B. lactis erythrogenes. (See figure.) Still all the biological 

 characters were normal, even the peculiar eff"ect on milk, but there 



Annals X. Y. Acad. Scl, VIII., May, 1895.— 24 



