752 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Production of Glycogen in Fungi.* — In fungi as in vascular 

 plants the production of reserve carbohydrates is connected with the 

 supply of sugar or analogous substances. Eniile Laurent has proved an 

 abundant formation of glycogen in Mucor racemosus, Sclerotinia Liber- 

 tiana, Botrytis cinerea, and Saccharomyces Gerevisice, grown in a very 

 diluted organic solution to which was added 1 part in 1000 of oxalic 

 acid and 1 part in 2000 of hydrochloric acid. The author suggests the 

 interpretation that the plant absorbs the carbohydrate nutriment more 

 quickly than it assimilates it, hence the presence of the reserve. In 

 a different medium, where growth of the filament was more rapid, the 

 production of glycogen was greatly diminished. 



Production of Acids by Fungi. f— Berthold Heinze reviews the 

 work that has been done in reference to acid formation during the 

 process of fermentation, and gives results of cultures carried on by 

 himself with a view to testing the results that have been arrived at by 

 others. He grew Phoma Beta, Aspergillus niger, Penic ill turn glaucum, 

 and Mucor stolon if er in a culture solution with ammonium sulphate 

 added to supply nitrogen. Acids were produced in every case ; acetic 

 acid and oxalic acid more particularly by Aspergillus niger. The writer 

 draws various deductions from the facts observed by him. lie proposes 

 to curry the research further. 



Bacteriophagous AcrasieaB.J — Paul Yuillemin cultivated Dictyo- 

 stelium mucoroides in tubes, and found constantly present a fluorescent 

 bacterium which he succeeded in isolating. A pure culture of Dictyo- 

 stelium spores did not grow until the bacterium was re-introduced. 

 Microscopic examination showed the bacillus engulfed and absorbed by 

 the amceboe. The pyocyanic bacterium was introduced into one of the 

 cultures with negative results. This bacterium has alkaline properties, 

 so it would seem that it is not alkalinity of nutriment that is secured 

 for the Acrasim by the bacterium, but that it is a necessary food. 



Acrasieae.§ — Edgar W.Olive has issued his monograph of the 

 members of the group. He gives an introductory historical account of 

 them and describes fully their life-history, comparing them with allied 

 « n'ganisms. The amcebse divide after issuing from the spore by indirect 

 division, though details of this have not all been worked out. After 

 some time a secondary division takes place, and it does not seem to be 

 accompanied by nuclear changes. Special study was made of their nutri- 

 tion, and though they undoubtedly inclose and absorb bacteria, yet the 

 writer concludes that nourishment is mainly absorbed in liquid form and 

 that the ingestion and digestion of solid food-particles is exceptional. 

 The aggregation of the myxamcebae and the formation of the fructifying 

 stage are described, and the results of experiments on the irritability of 

 the pseudoplasmodium are given. Finally the author gives a review of 

 their systematic relations, and a classification of the genera and species. 



* Comptes Rendus, exxxvii. (1908) pp. 451-3. 



t Ann. Mycol., i. (1903) pp. 344-53. 



\ Comptes Rendus. exxxvii. (1903) pp. 387-89. 



§ Proc Boat. Soc. Nat. Hist., xxx. (1902) pp. 451-513 (4 pis.). 



