November 30, 1917] 



SCIENCE 



545 



ornithine derived from arginine. The analyses 

 furnish no evidence as to whether or not these 

 "acids" are true chemical compounds or as to 

 whether or not their structure is more simple than 

 is that of egg albumen. The paper will appear in 

 the Jour. Amer. Chem. Soc. 



The effect of prolonged add hydrolysis on the ni- 

 trogen distribution of fibrin with especial reference 

 to the ammonia fraction: Ross Aiken Gortner 

 and George E. Holm. Fibrin was boiled with 20 

 per cent. HCl for varying periods of time ranging 

 from 1 hour to 6 weeks, the ammonia fraction in- 

 creases continuously showing a 150 per cent, in- 

 crease at the end of six weeks over that obtained 

 at the end of twelve hours. This increase in am- 

 monia comes almost entirely from the deamination 

 of mono amino acids. The ammonia fraction of a 

 twenty-four or forty-eight-hour hydrolysate can 

 not be taken as an absolute measure of amide 

 nitrogen for some "deamination" nitrogen is un- 

 doubtedly present, the amount depending both 

 upon the particular protein and the length of hy- 

 drolysis. The paper will appear in the Jour. Amer. 

 Chem. Soc. 



Comparative analyses of fibrin from different 

 animals: Ross Aiken Gortner and Alexander J. 

 "WuERTZ. Fibrin has been prepared from the 

 blood of cattle, sheep and swine and the nitrogen 

 distribution determined by Van Slyke's method. 

 No differences significantly greater than the ex- 

 pected experimental errors were found. It would 

 thus appear that fibrin from any of these three 

 sources can be used interchangeably in experi- 

 mental work without invalidating the results. 

 Whether or not this is true for fibrins from other 

 sources remains still an open question. The paper 

 will appear in the Jour. Amer. Chem. Soc. 



The nitrogen distribution of fibrin hydrolyzed 

 in the presence of ferric chloride: Clarence Aus- 

 tin Morrow. When a protein is hydrolyzed in the 

 presence of ferric chloride an accurate nitrogen dis- 

 tribution can not be obtained. There is a substan- 

 tial increase in the ammonia N, due probably to 

 deamination of amino acids at the higher temper- 

 ature of hydrolysis. The acid soluble humin in- 

 creases at the expense of a corresponding loss from 

 the "filtrate from the bases," thus indicating 

 that the earlier conclusion regarding the soluble 

 humin N of soils was incorrect and that this frac- 

 tion of a soU hydrolysis may be of protein origin. 

 Since hydrolysis in the presence of either carbo- 

 hydrates or ferric chloride radically changes the 

 nitrogen distribution of proteins, it is obvious that 



no accurate knowledge of soil proteins can be ob- 

 tained by applying Van Slyke 's method to soils. 



A new form of ultra-filter; its uses in synthetic 

 and biological chemistry: P. A. Kober. A new 

 form of ultra-filter is described which depends on 

 pervaporating both dialysis and diffusate solution 

 during dialysis. Its usefulness in filtering off 

 humus and other coloring matter in biological work 

 and organic synthetic work, as well as colloids in 

 general, is pointed out. The apparatus makes it 

 possible now, for the first time, to dialyze quanti- 

 tatively. 



Studies on Piper bredemeyeri, an adulterant of 

 matico: A. Viehoever and M. G. Mastin. A 

 study has been made of the volatile oil obtained 

 from Piper bredemeyeri, an adulterant of matico. 

 Piper angustifolium. It was found that the 

 volatile oil did not yield asaron, which is obtained 

 from genuine matico, nor matico camphor, ob- 

 tained from Piper angustifoliiim var. ossanum. 

 The oil from Piper bredemeyeri, containing over 

 50 per cent, of dillapiol, was very similar in com- 

 position to that reported to be obtained from 

 Piper mandoni. The chemical and botanical simi- 

 larities suggest that the name Piper mandoni has 

 been given to plants belonging to the species Piper 

 bredemeyeri. A paper on the subject is in prep- 

 aration. 



Studies on mustards and mustard substitutes: 

 A. Viehoever, C. O. Ewing and J. F. Clevenger. 

 Work on monographs of mustards and mustard 

 substitutes has progressed considerably. New 

 supplies from India, China and Japan have been 

 identified on the basis of studies including the 

 botany and chemistry of the seeds, and also 

 studies of plants grown from the seeds. Ma- 

 terial of Indian brown mustard proved to be sub- 

 stituted by Indian rape or tori, Brassica napus 

 var. dichotoma. Chinese mustard, Brassica juncea, 

 was found to be usually improperly collected, 

 containing a considerable amount of immature 

 seeds and weed seeds, including generally Eruca. 

 A preliminary study of the volatile oils obtained 

 from Chinese mustard, Brassica juncea, and Jap- 

 anese mustard, Brassica cernua, indicates that 

 they are mixtures containing only in part allyliso- 

 thiocyanate. The volatile oil from Brassica cam- 

 pestris sativa chinensis, another adulterant of 

 mustard, proved to be crotonylisothiocyanate. 

 This oil has no mustard qualities. Since the plant 

 grows very vigorously, plans are under way to 

 utilize it either for greens and salads or for stock 



