1918] Coccobacillus Acridiorum D'Herelle 33 



FIELD EXPERIMENTS. 



Melanoplus atlanis is a serious pest in certain regions of the 

 State of Vermont. Since this species occurs in dense swarms 

 and since it acquires cannibaHstic habits when natural food 

 becomes scarce, I thought it would be splendid material for 

 field work. Mr. A. M. Wilcox and I have instituted a large 

 series of field experiments with cultures "Souche Cham" and 

 "Souche Sidi" in Vermont, but we wish to await the passage 

 of at least another season before drawing any conclusions. The 

 hurried method of rushing into print field observations dealing 

 with a single season's work is deplorable. The amount of work 

 which is necessary before coming to any conclusions at all is 

 s.o immense that an army of trained workers co-operating in 

 every possible way could not obtain final results after a single 

 season's work. 



Culture sent by Dr. Cicilio Lopez Ponce of Honduras under the 

 name of Coccobacillus acridiorum: 



Bacillus poncei sp. nov. 



Morphology. From 13^% nutrient agar stroke 24 hours old, long 

 rods. From 13^% potato agar stroke 24 hours old, long rods and some 

 short rods. From milk 48 hours old, many short rods. Average length 

 2.2/x. Average width .9/x. Motile. Gram negative. Stains readily. 



Nutrient agar stroke. l}4%. Neutral. Growth moderate, spread- 

 ing, flat, glistening, smooth, white, opaque, odor absent, butyrous, 

 medium unchanged. 



Potato agar stroke. 13^%. Neutral. Growth very luxuriant, 

 arborescent, flat, glistening, smooth, white, opaque, odor absent, 

 butyrous, mediimi unchanged. ' 



Potato. Growth abundant, spreading, flat, glistening, smooth, 

 white, odor absent, butyrous, medium unchanged. 



Gelatin stab. Growth best at top, beaded, no liquifaction, medium 

 unchanged. 



Nutrient broth. Neutral. Pellicle, clouding strong, no clearing 

 after 15 days, odor absent, slight sediment. 



Milk. Acid. Coagulation in six days. Extrusion of whey in 

 six to ten days, no peptonization, color of medium unchanged. 



Litmus milk. Acid, coagulation, prompt reduction. 



Gelatin colonies. Growth slow, white, round, slightly raised, edge 

 entire, no liquifaction. 



Agar colonies. Growth slow, white, round, smooth, raised slightly, 

 edge entire, amorphous, diameter 4 mm. 



Ammonia production. Feeble. 



