304 EXPEKIMENT STATION KECOKD. 



it is seen that they really deal with three separate things — the rate of am- 

 monia production in soil, the rate of nitrification in soil, and the rate of nitrifi- 

 cation in a culture solution. In these circumstances it is not surprising that 

 concordant results have not been obtained. When ammonium salts react with 

 soil a certain proportion enters into a stable combination which is not decom- 

 posed on distillation with alcoholic potash or magnesia and is therefore not 

 an ammonium compound. Its constitution has, however, not been determined.^' 



Vegetable proteins, T. B. Osborne, trans, by Helene Schlesinger {ErgcJ). 

 Physiol., 10 (1910), pp. Jfl~215, figs. 7). — In this publication the author presents 

 the work done in the field of the chemistry of the vegetable proteins, and which 

 includes much of his own work (E. S. R., 22, p. 509; 23, p. 410). The subject 

 is treated from the standpoint of the proteins, and their ultimate cleavage 

 products as they occur in the individual seeds or plants. 



The partial hydrolysis of proteins. — II, On fibrin-heteroalbumose, P. A. 

 Levene, D. D. Van Slyke, and F. J. Birchaed {Jour. Biol. Chcm., 8 {1910), 

 No. If, pp. 269-284)- — The authors report work on the preparation and hydrolysis 

 of hetero-albumose. Out of a total of 58.05 parts of amino acid obtained from 

 100 parts of albumose, glutaminic acid constituted 9.51, prolin 4.27, aspartie 

 acid 4.73, arginin G.35. lysin 4.S0, and eystin 4.10 pai-ts. 



On the refractive indexes of solutions of certain proteins. — II, The para- 

 nucleins, T. B. Bobertson (Jour. Biol. Chem., 8 (1910), No. Jf, pp. 287-295). — 

 " The refractive indexes of solutions of paranuclein, prepared from casein in the 

 manner described in the body of the iraper, are connected with their concen- 

 trations by the formula n — ni=flXc, where n is the refractive index of the 

 solution, ni is the refractive index of the solvent, in this instance fiftieth- 

 normal potassium hydroxid (1.3334 at 22°), c is the percentage concentration 

 of the protein in the solution, and c is a constant which is numerically equal to 

 the change in the refractive index of the solvent which is brought about by dis- 

 solving 1 gm. in 100 cc. The same law has previously been shown to hold good 

 for solutions of casein and of ovomucoid in various solvents. 



"The value of a, in the above formula, for paranuclein is 0.00140. 'Para- 

 nuclein A' is prepared from paranuclein by partial digestion with calcium 

 hydrate and differs from it mainly in its lower phosphorus content. It is im- 

 possible to distinguish between paranuclein and Paranuclein A by the change 

 which their presence causes in the refractive index of an alkaline solution, since 

 for this substance the value of a is also 0.00140. 



" [The author has] previously shown that a substance is synthesized through 

 the action of pepsin at 36" upon the concentrated products of the complete 

 peptic hydrolysis of casein which closely resembles Paranuclein A in its proi^er- 

 ties. It is shown in this paper that it also resembles Paranuclein A in its effect 

 upon the refractive index of an alkaline solution, the value of a for this sub- 

 stance being also 0.00140. 



" [The author has] previously shown that a substance is synthesized through 

 the action of pepsin at 60° vipon the unconcentrated products of the com- 

 plete peptic hydrolysis of casein, which is apparently identical with the above- 

 mentioned substance and with Paranuclein A. In this paper it is shown that 

 for this substance also the value of a is 0.00140. 



" These data may be regarded as affording confirmation of the view that the 

 above-mentioned substances, synthesized through the action of pepsin from the 

 products of the complete peptic hydrolysis of casein, are members of the para- 

 nuclein group." 



On the differentiation of proteins of closely related species by the precipi- 

 tin reaction, D. A. AVelsh and H. G. Chapman (Jour. Hyy. [Cambridge], 10 

 (1910), No. 2, pp. 177-18-'f). — "It is possibleclearly to distinguish heterologous 



