Feb. i6. 1920 Basal Glumerot of Wheat 549 



and the minimum is below 2°. The thermal death point is between 48° 

 and 49°. 



Desiccation. — Bacteria from 24-hour beef bouillon cultures, spread 

 on sterile cover glasses and kept in the dark, were nearly all dead inside 

 of 24 hours. A few grew after 7 days' drying. 



Bacteria from 7-day-old agar cultures showed more resistance and 

 were alive on the ninth day after being put on covers. A few were alive 

 on the twelfth day, and one culture was secured after 26 days. The 

 organism has been isolated from dry wheat kernels kept at room tem- 

 perature for 17 months. 



Optimum reaction in beef bouillon. — The organism grows well in 

 peptonized beef bouillons titrating from o to — 14 on the alkali side and 

 to -f 30 on the acid side. Beyond these limits the growth was feeble or 

 lacking. Sodium hydrate was used for the alkali and hydrochloric for 

 the acid. These were inoculated rather heavily from 2-day-old beef 

 bouillon cultures. 



Effect of sunlight. — Five minutes' exposure to sunlight, on ice, 

 killed about 50 per cent of the organisms in agar plates. Ten minutes' 

 exposure caused a reduction of from 95 to loo per cent. 



Effect of freezing. — Several tests were made, (i) Freshly inoc- 

 ulated beef bouillon cultures were frozen for two hours. The reduction 

 of the organism was 70 to 75 per cent. (2) Five hours ' freezing caused 

 a reduction of from 84 to 100 per cent. (3) Forty-four hours' freezing 

 killed 80 to 100 per cent. 



NAME OF ORGANISM 



This organism appears to be an undescribed form, and because of the 

 brown to black discolo rations which it causes at the base of the wheat 

 kernels and glumes the name Bacterium atrofaciens , n. sp., is suggested. 



TECHNICAL DESCRIPTION 



Bacterium atrofaciens, n. sp.' 



Rods, cylindrical, rounded at ends. Individual rods i to 2.7/i by o.6jtt. In 

 liquid media, moderately long filaments (3 to 30 bacteria). Motile by i to 4 polar 

 flagella; aerobic, no spores; capsules in beef agar cultures. 



Surface colonies in peptone-beef agar plates are round, smooth, shining, and with 

 inconspicuous internal striations, somewhat irregtilarly concentric in arrangement, 

 white becoming greenish, the surrounding medium also becoming greenish. 



' Bacterium atrofaciens, sp. nov. 



Baculis asporis, aerobiis. Capsulas in culturis agar-agar habentibus. Baculis singularibus 1-2.7^X0.6**. 

 1-4 flagellis polaribus mobilibus. In ctilturis liquidis 3-30 baculis in filamentis conjunctis. Coloniis albis, 

 rotiindis, nitentibus, et in agar-agar cum striis inconspicuis intemis, aliquid irregularitcr concentricis; 

 Culturae et coloniae virescentes. 



Gelatinam liquefacit. Nitrura non redigitur. Lac sterile alcalinum fit, non coagulatur. Saccharum 

 sacchari, saccharum uvae, ct saccharum galacti acidum fit; gas non fit. Baculi methodo Gram non color- 

 antur. 



Habitat in foliis, glumis, et grauis Tritici vulgaris. Maculas fuscas in basi glumarum granorumquc facit. 



