REVIEWS 361 



plant nucleic acids is invariably found to be the pentose ^/-ribose. Partial 

 hydrolysis of these nucleic acids gives rise to substances known as nucleotides, 

 in which a carbohydrate group links together phosphoric acid with a purine 

 or pyrimidine base, while ferment action produces from nucleic acid the so-called 

 nucleosides which are composed of one of these nitrogenous ring compounds coupled 

 to a carbohydrate complex. These facts have led to the conclusion that the nucleic 

 acids are in reality tetra- nucleotides, that is to say are compounds produced 

 by linking together four different nucleotides containing as their nitrogen bases 

 either guanine, adenine, cytosine and thymine or guanine, adenine, cytosine and 

 uracil, according as they are of animal or plant origin. The author's views con- 

 cerning the vexed question of the origin of urinary uric acid may be gleaned from 

 the following quotation : " If one is inclined to believe that uric acid is not 

 formed in the body from nucleic acid, he should at least note that the organism is 

 equipped with a mechanism that can effect all of the transformations necessary 

 to its formation." Much useful information concerning the preparation of the two 

 nucleic acids and their derivatives and the demonstration of the purine ferments is 

 contained in the appendix. 



The author has succeeded in reviewing this most difficult subject in a very able 

 manner, applying his criticisms in an impartial, though at times humorously caustic 

 manner. 



P. H. 



The Simpler Natural Bases. By George Barger, M.A., D.Sc. [Pp. viii + 

 216.] (London : Longmans, Green & Co., 1914. Price 6s. net.) 



With the discovery of the physiological action of extracts of putrid meat upon the 

 blood pressure and the isolation by Barger and Walpole of the active bases 

 isoamylamine and p-hydroxyphenylethylamine from these extracts, the investi- 

 gation of the chemistry of putrefaction received a great stimulus. Subsequent in- 

 vestigation proved that these bases were produced by decarboxylation of amino 

 acids derived from protein, and a systematic search was therefore undertaken 

 for the amines corresponding to the other fission products of proteins ; it 

 was thus found that the activity of ergot was due principally to p-hydroxyphenyl- 

 ethylamine and /3-imidazoIyl-ethylamine, the amine corresponding to histidine. This 

 discovery has since been put to practical use inasmuch as /3-iminazolyl-ethylamine 

 is at the present time being manufactured commercially by bacterial decarboxyla- 

 tion of histidine. 



In view of the extensive literature which has grown up around the substances 

 within the last few years a summary of our present knowledge of this subject is to be 

 welcomed. The title chosen for the monograph having no precise chemical 

 significance, the author has been compelled to use his own judgment in determining 

 what substances should be included under this heading, with the result that the 

 purine bases have been omitted. This decision, in some ways regrettable, was no 

 doubt wise in view of the fact that the monograph has already attained considerable 

 proportions. The subject-matter has been divided into seven chapters, the first 

 three of which deal with bases derived by slight modifications from the constituent 

 units of protein, while the remaining chapters deal successively with choline 

 and allied substances, creatine, creatinine and guanidine, etc., adrenaline and 

 a group of bases of unknown constitution. The enormous mass of literature on 

 creatine and creatinine and also on adrenaline has been very skilfully summarised 

 and made into a more or less connected story, the value of which is considerably 

 enhanced by the addition of a very complete bibliography. Perhaps the most 



