218 Physiologie. 



It is probable, in the light of earlier studies of the date, that 

 the above conclusions are applicable to this fruit also. Moore. 



Me Pherson, The formation of carbohy drates in the ve- 

 gatable kingdom. (Science N. S. XXXIII. p. 131—142. Jan. 27, 

 1911.) 



Address of the vice-president and chairman of Section C. — 

 Chemistry — at the Minneapolis meeting of the A. A. A. S. An 

 historical discussion of the more important investigations on the 

 subject under the following heads. Production of formaldehyde 

 through the reduction of carbonic acid; the existence of formalde- 

 hyde in plants; the assimilation of formaldehj^de by plants; synthetic 

 production of sugar from formaldehyde. Moore. 



Petrie, J. M., Röle of Nitrogen in Plant-Metabolism. Parts 

 III — V. (Linn. Soc. N. S. Wales, Abstr. Proc. p. 1-2. April 26. 1911.) 



III. The Distribution of Nitrogen in the Seeds of Acacia pycnantha. 

 The seeds contain 4-51 ü / of N in various forms; 26'6°/ of the total 

 N is contained in protein extractable by water, 13 - 3°/ is soluble in 

 10°/ saline Solutions; no alcohol-soluble proteins are present, 15T°/ 

 is unextracted by solvents, and 45°/ is in the form of other water- 

 soluble Compounds, which are not precipitated by protein reagents. 

 The changes in the solubility of the protein are examined in various 

 stages of partial neutralisation. A comparative study of the action 

 of various protein precipitants is made, and the literature referring 

 to the nature of the precipitates is reviewed. Quantitative precipi- 

 tation by alcohol of increasing strength brings out a differentiation 

 of the N values, and shows the presence of at least two different 

 proteins. The results are shown \>y a curve. The protein-free Solu- 

 tion contains (1) substances which very easily set free ammonia 

 when distilled; (2) other Compounds which liberate ammonia only 

 when hydrolysed with dilute acids; (3) Compounds which are only 

 decomposed by boiling with strong acids for prolonged periods, 

 and yield their ammonia gradually when distilled; (4) basic Com- 

 pounds, including the xanthin group and cholin. The N of amino 

 Compounds is estimated in the various stages. The nature of these 

 non-protein N. Compounds is extensively discussed in the paper. 



IV. The Nitrogen of Ripening Seeds. Experiments on the wild 

 tare, Vicia sativa, are described. It is shown that the seeds, as 

 ripening progresses, gain in protein and also in non-protein N Com- 

 pounds, the mature seeds containing the largest amount of each. 

 The present generally accepted view, that the proteins are formed 

 at the expense of non-protein N Compounds, is not supported by 

 the results. On the contrary, all ripe seeds examined contain a 

 considerable amount of non-protein N which remains practically 

 unaltered troughout the dormant State. If this consisted of plastic 

 material we should expect it to be almost entirely consumed in the 

 ripe seed. A second series of experiments on Vicia faba showed 

 that when the seeds are left for definite times enclosed in the 

 isolated pods, a transference of material takes place from the pods 

 to the seeds. This results in a large increase in total N and protein 

 N, and a small increase in non-protein N. The conclusion is, there- 

 fore, that the seed-protein could only have been augmented by the 



