7 6 BOTANICAL GAZETTE [january 



these organisms to light, oxygen, and organic substances. With regard to light, 

 the purple bacteria do not ordinarily show positive phototaxis, but are incited 

 to motility which continues for some time after the light is removed. They are 

 not able to obtain carbon from carbon dioxid in the presence of light. Some 

 forms are even anaerobic, and, unlike most pigment bacteria, can produce pigment 



under this condition. 



distingu 



the red (bacteriopurpurin) and a green (bacteriochloriri). The latter is distinct 

 from cholorophyll, which fact agrees with that of their inability to use C0 2 . 

 Molisch concludes that nutrition from organic substance is somewhat related 

 to light and the presence of pigment as shown by the increased energy caused 

 by light; and that thus these forms stand between the colorless bacteria and 

 the green algae. — Mary Hefferan. 



The typhoid-coli group of bacilli. — Numerous methods have been proposed 

 for the ready separation and identification of the typhoid and the colon bacilli in 



water. 



MacConkey 



CONRADI 



been more or less successful in the hands of various workers. These are based 

 upon substances which restrain the growth of one type of organism while allow- 

 ing a characteristic development of the other. Ducamp* proposes for this purpose 

 the use of an "antibacilliary" broth prepared by cultivating in a lactose-peptone 

 solution several strains of B. coli, for example, derived from different sources. 

 This broth, when finally filtered germ-free, will be exhausted as a medium for 

 B. coli, but will still allow the growth of B. typhosus. For the rapid detection of 

 the latter in water, the sample is first plated in phenol broth and inoculations 

 made from the colonies into lactose broth. If a race thus obtained grows in the 

 anticoli and not in the antityphoid broth, and is agglutinated i : 50 by typhoid 

 serum, it is undoubtedly B. typhosus. 



Studies on the fermentative activities of the typhoid -coli -dysentery group 

 resulted in the confirmation of some facts already known, and brought out some 

 new affinities. B. par a- typhosus, B. enteritidis, B. psittacosis Danysz and 

 Thomassen, and hog cholera ferment the same sugars except for two races of hog 

 cholera, which are inactive on xylose, dulcite, and mannose. B. para-typhosus 

 Kurth in addition ferments saccharose and raffinose. B. para-typhosus A differs 

 with respect to xylose, mannose, and dulcite.— Mary Hefferan. 



NOTES FOR STUDENTS 



Subterranean fungi.— Ed. Fischer has recently made a contribution 5 to the 

 morphology of the fungi. The paper is based on the study of material collected 



4 Dxjcamp, Louis, Contribution a l'etude de la differentiation du colibacille et du 

 bacille typhique. Action des bacilles du groupe coli-typho-dyssenterique sur les 

 hydrates de carbone. pp. 181. pi. i. Thesis. Lille. 1907. 



s Fischer, Ed., Zur Morphologie der Hypogaeen. Bot. Zeit. 66: Hi" 168 ' 



pi. 6. 1908. 



