March, 1922. 



SCIENTIFIC AGRICULTURE 



221 



granules float in the liquid and also are to 

 be seen attached to the remaining curd. 



Idtmus Milk at STi/o deg. C. — In 24 

 hours acid ; distinctlj^ acid after one month. 

 In this medium the reactions are identical 

 with those recorded above — see milk at 

 371/2 f^Pg- ^- — except that the litmus ap- 

 pears to exert a slightly inhibitivo effect 

 on the activity of the organism. 



Milk + Peptone. — In this medium the 

 reactions are identical witlh those recorded 

 above — see milk at SJi/o deg. C. — except 

 that the dissolving proceeds at a more rapid 

 rate. 



Temperature Relations. — Thermal death 

 point 10 minutes exposure in nutrient 

 broth at 58 deg. C. Optimum temperature 

 37I/2 deg. C. ; cultures incubated at STi/j 

 C, and room temperature respectively. 



Chromogenesis. — In nutrient broth at 

 371^ deg. C, no pigment in one week. In 

 nutrient gelatin at room temperature, yel- 

 low along track of needle in 6 daj's. On 

 nutrient agar at Siy^ deg. C. surface col- 

 onies pale yellow; deep colonies brighter 

 yellow in 2 days. On potato, in 24 hours 

 37I/0 deg. C, pale yellow. Growth from 

 agar slants, which had been incubated for 

 two weeks at room temperature, spread 

 thickly on white paper and dried, matched 

 Cadmium Orange Chrome IV of the fron- 

 tispiece of " Systematic Relationships of t^e 

 Coccaceae" by Winslow and Winslow (28) . 



Relation to Oxygen. Facultative anae- 

 robe. 



Biochemical Reactions. Indol not pro- 

 duced. Nitrates not reduced or only to a 

 very slight degree. 



Fermentation of Carbohydrates. — Dex- 

 trose, lactose, galactose, saccharose, levu- 

 lose, maltose, mannite, raffinose, and gly- 

 cerin are fermented to acid within 24 

 hours. The reaction to mannite and raf- 

 finose is but slight. Inulin is not ferment 

 ed. Gas is not produced from any of the 

 carbohydrates used. 



The characteristics of this organism 

 which have been determined, lie within th« 

 variations included by Conn, Esten and 

 Stocking in the type M. lactis varians, (6) 

 noted by them as the most common coccus 

 found in milk, and frequently present in 

 milk directly from the udder. These work- 

 ers were led to consider that their type was 

 the common Staphylococcus pyogenes au- 

 reus, and therefore in harmony with the 



more recent classification of the Comni. of 

 the Society of Amer. Bact. (29) and of 

 Winslow, Rothberg and Par.sons, (23) and 

 following Buchanan (35) the Culture 63 is 

 to be classified as of the type Staphylococ- 

 cus aureus (Rosenbach). 



Culture 126, isolated from middle milk 

 of Cow 135, is a rod with rounded ends oc- 

 curring singly or in chains; variation in 

 size is shown, according to the age of the 

 culture and the medium employed. The 

 organism is Gram positive and forms spo- 

 res. From the condensation water of agar, 

 young cultures are actively motile. 



On agar at 37i/o deg. C, the growth is 

 luxuriant and spreading. At 21 deg. C. 

 gelatin is liquefied, stratiform. In milk at 

 37I/2 deg. C. no apparent change can be 

 noted in 24 hours; in 48 hours there is a 

 soft clot beginning to dissolve stratiform, 

 with no odor ; in 6 days the dissolving has 

 proceeded to the extent of three-fourths of 

 the whole, and a putrid odor can be defin- 

 ed ; later, a sweet putrid odor is noted, and 

 in two months a pronounced "beef ex- 

 tract" odor is apparent. In litmus milk 

 at 3TY2 deg. C. the reactions proceed as 

 above; as indicated by the litmus, acidity 

 is first noted, bleaching then takes place, 

 and later, distinct alkalinity is evident. In 

 milk + peptone at 371/2° C., the reactions 

 are very similar to those recorded for milk. 

 In milk at room temperature, dissolving is 

 less rapid than at 37i/o deg. C. but is com- 

 pleted in 24 days. In milk at 15 deg. C. the 

 dissolving is delayed; in four weeks, slight 

 dissolving can be noted, with a putrid odor ; 

 -later a soft clot is formed which in 7 weeks 

 is one-half dissolved. In dextrose, lactose, 

 galactose, saccharose, levulose, maltose, 

 mannite, raffinose, glycerin, and inulin, 

 acid is formed within 24 hours. The re- 

 actions to galactose, mannite and inulin, 

 are slight. Gas is not produced. 



After a detailed study of the morpho- 

 logy, method of sporulation, size, shape 

 and position of the spore, the reactions to 

 gelatin, litmus-milk, glucose, lactose and 

 saccharose broth, and to glucose-litmus- 

 agar, we consider this organism identical 

 with the strain classified by Lawrence and 

 Ford (36) as Bacillus albolactis Migula. 



Culture 127, isolated from fore-milk of 

 Cow 56, is a Gram positive rod, without 

 endospores, occurring singly or in chains 

 and showing great variation in morphology 

 according to the age of the culture, and 



