New York Agricultural Experiment Station. 181 



In 1910, while associated with the Cornell University Agricultural 

 Experiment Station at Ithaca, N. Y., the writer first called atten- 

 tion to the fact that the number of bacteria in frozen soil is greater 

 than in unfrozen soil. 6 The following winter more data were col- 

 lected and all were published in a second article 7 appearing in 1911. 

 For the sake of comparison with the results obtained at Geneva 

 during 1912-14, the Ithaca work must be summarized here. 



Table I. — Bacterial Counts of FrELD Soil. 

 Samples taken at Ithaca, N. Y. 



Date. 



Bacteria Per Gram Dry Soil, in — 



plat 4b 



Center. 



North end. 



plat 1b 



Center. 



North end. 



April 17 

 May 25 

 July 16 

 Sept. 16 

 Oct. 8 

 Nov. 23 

 Jan. 21 

 Feb. 7 

 Feb. 26 

 Mar. 25 

 April 15 

 May 28 

 June 15 

 July 2 

 Aug. 20 

 Sept. 14 

 Oct. 12 

 Nov. 12 

 Nov. 30 

 Dec. 19 

 Jan. 

 Jan. 

 Feb. 

 Feb. 

 Mar 

 Mar. 29 

 April 12 



1909. 



1909. 



1909. 



1909. 



1909. 



1909. 



1910. 



1910. 



1910. 



1910. 



1910. 



1910. 



1910. 



1910. 



1910. 



1910. 



1910. 



1910. 



1910. 



1910. 



1911. 



1911 



1911 



1911 



1911 



1911 



1911 



7,000,000 



3,300,000 



5,000,000 



10,000,000 



9,200,000 



6,800,000 



10,000,000 



23,500,000 



33,000,000 



5,700,000 



12,000,000 



7,000,000 



14,000,000 



13,000,000 



8,500,000 



9,500,000 



7,000,000 



7,000,000 



4,000,000 



9,500,000 



7,000,000 



23,000,000 



15,500,000 



15,000,000 



tl4,000,000 



23,000,000 



22,000,000 



116,000,000 



14,000,000 



18,000,000 



10,000,000 



4,500,000 



*22,000,000 



8,000,000 



5,750,000 



13,000,000 



27^000^000 



6,700,000 



2,500,000 



12,000,000 



16,500,000 



9,000,000 



15,000,000 



13,000,000 



2,000,000 



7,000,000 



6,000,000 



5,900,000 



7,000,000 



17,500,000 



20,000,000 



10,000,000 



27,000,000 



21,000,000 



28,000,000 



7,500,000 



20,000,000 



*This count is probably too high, as little but surface soil was included in the sample, 

 t These counts are inexact, because of the extremely rapid liquefaction of the plates. 



6 Conn, H. J. Bacteria in Frozen Soil. Centbl. Bakt. Abt. II, 28:422-434. 1910. 

 7 Conn,H.J. Bacteria of Frozen Soil. II. Centbl. Bakt. Abt. II, 32:70-97. 1911. 



