850 EXPERIMENT STATION RECORD. 



In other parts of the work bacteria as applied to the transformation of vege- 

 table and animal products are discussed under the headings of fermentation, 

 vinegar manufacture, starch manufacture, baking, fruit and vegetable preser- 

 vation, silage, flax retting, tobacco fermentation, and the bacteria of the dairy, 

 tannery, etc. 



On proteolytic enzyms, II, A. L. Dean (Bot. Got.. 40 (1905), No. 2. pp. 121- 

 134). — ^ study was made of the proteolytic enzyms of beans to determine the 

 distribution of erepsin. 



The results of the investigations show that the proteids of the seeds of beans 

 undergo proteolysis during germination, as a preliminary to the transportation 

 of the nitrogen and its utilization in the formation of new organs. The author 

 says there are 3 ways in which this process may be carried out — by the action of 

 a tryptic enzym, by the combined action of the protoplasm and of an enzym 

 which by itself is incapable of carrying out the whole process, or by the action of 

 the protoplasm alone. 



The results of his studies of the resting and germinating beans show that 

 there is no enzym present which is able to digest the proteids of the seed. 

 There is present, however, an enzym of the ereptase group which is capable of 

 digesting the proteoses resulting from the partial hydrolysis of the seed proteids. 

 It is believed possible, therefore, that the protoplasm of the cells starts the pro- 

 cess of proreid decomposition and carries it to some stage at which the ereptase 

 takes up the work and completes the process. 



On the structure and biology of the yeast plant, F. Mutchler (Jour. Med. 

 Research. 14 (1905), No. /. pi>. 13-50, pi. 1). — The author describes investiga- 

 tions on the structure and biology of the yeast plant ( Saccharomyces cerevisice), 

 in which some important discoveries relative to the yeast plant were determined. 



The author reports the presence of a relatively large nucleus, a definitely 

 marked nuclear membrane, and characteristically differentiated granules and a 

 reticulated network within the nucleus, which stains in every way as do the 

 nucleoli of the cells, and the young cells are said to have the same organization 

 as the more mature ones. 



In studying the biology of the yeast plant the author experimented with pure 

 cultures in various culture media, in which the effect of various agents upon 

 growth was determined, and he concludes that from his investigations S. cere- 

 visiw is not a variable species, and any variation in form observed is due to the 

 inherent nature of the cell rather than to external conditions. Variation in the 

 size and rate of growth of cells may be produced by changes in the conditions 

 under which they grow, and anesthetics do not permanently destroy growth or 

 reproduction of this species. 



Synthetic culture media and the biochemistry of bacterial pigments, M. 

 X. Sullivan (Jour. Med. Research, 1) (1905). No. 1. pp. 109-160). — The 

 author reports upon a series of investigations in which he undertook to grow 

 bacteria in nutrient media of very simple composition and to also determine the 

 conditions under which bacteria develop their pigments. 



The experiments show that bacteria can in a great measure be grown on very 

 simple media, and that from these simple combinations the micro-organisms 

 can elaborate not only the protoplasm they require but also materials which 

 pass through a porcelain filter and gives reaction for albumins. Not only can 

 bacteria synthesize" complex bodies from simpler compounds, but they are able 

 to carry out their activity, producing pigment and in some cases forming fer- 

 ments or enzyms. It was found possible to develop in an organism the power 

 to grow on simple salts, either by accommodating the medium to the organism 

 or adapting it to the medium. 



