1918] ' Coccobacillus Acridiorum D'Herelle 23 



The cultures were supposed to represent d'Herelle's Cocco- 

 bacillus acridiorum and Dr. Ponce claimed to have obtained 

 striking results with them in his field experiments. 



During February, 1917, I received two cultures of the sup- 

 posed Coccobacillus acridiorum direct from Dr. F. d'Herelle 

 who is now at the Pasteur Institute, Paris. One culture was 

 labeled "Souche Cham" which d'Herelle informed me is 

 identical with the one I received from Dr. Ponce of Honduras. 

 The other culture was labeled "Souche Sidi" and according to 

 d'Herelle represented a strain of Coccobacillus acridiorum passed 

 through a series of grasshoppers in Tunisia in 1915. 



Also in February, 1917, I received through the kindness of 

 Dr. C. Gordon Hewitt a pure culture of the supposed Cocco- 

 bacillus acridiorum from Messrs. Du Porte and Vanderleck, who 

 have performed some interesting experiments with this bacter- 

 ium in eastern Canada. Dr. Hewitt, in a letter to me, stated 

 that he received this culture direct from the Pasteur Institute 

 in Paris. 



I made a careful systematic study of these four cultures, 

 compared them with one another as well as with the published 

 descriptions of d'Herelle, and those of Du Porte and Vanderleck. 

 The cultures differ from one another more or less. A table on 

 page 25 shows the most salient differences and similarities. 

 Since the bacterium sent by Ponce from Honduras seems to be 

 an organism new to bacteriological literature, I have described 

 it as a new species and named it Bacillus poncei in honor of 

 Dr. Cicilio Lopez Ponce. I have also redescribed the three other 

 cultures.* 



Bacillus poncei is certainly not a Coccobacillus. It is a true 

 bacillus, not in the least pleomorphic, no matter on what media 

 it is grown. In this respect it certainly differs from d'Herelle's 

 description. The latter emphatically states that his organism 

 is highly pleomorphic, all stages between bacilli and cocci being 

 observed in the same pure culture. Bacillus poncei produces 

 much acid in milk; Coccobacillus acridiorum, according to 

 d'Herelle, strong alkalinity. In so far as the production of 

 ammonia and the fermentation (with gas) of dextrose, levulose 

 and maltose are concerned the two organisms agree. D'Herelle's 

 cultural and bio-chemical descriptions are so meagre that it is 

 difficult to ascertain his exact meaning. 



* The detailed descriptions will be found appended to this article. 



