3i6 



NA TURE 



^Feb. 4, 1 886 



OUR BOOK SHELF 



Studies from the Laboratory of Physiological Chemisliy 

 of the Sheffield Scientific School of Yale College for 

 1884-85. Edited by Prof. R. H. Chittenden, Ph.D. 

 (New Haven, 1885.) 



This volume of some 200 pages is a reprint from volumes 

 vi. and vii. of the Transactions of the Connecticut 

 Academy, which were published between March and No- 

 vember of 1S85. It contains eleven more or less important 

 physiological memoirs, the result of work done in the 

 Sheffield .Scientific School of Yale College by Prof. 

 Chittenden and his colleagues. The first memoir inves- 

 tigates the diastatic action of saliva as modified by 

 various conditions, studied quantitatively, the joint author 

 being Dr. Herbert Smith. The second is on the amylo- 

 tic action of diastase of malt as modified by various 

 conditions studied quantitatively, the joint author being 

 Dr. Cummins. Diastase taken into the stomach must 

 sooner or later be completely destroyed by either the free 

 acid or the large percentage of acid proteids ; but in the 

 first stage of digestion, in the absence of free acids and 

 under the protecting influence of proteid matter, the 

 conversion of starch into sugar may still go on, though 

 soon destined to feel the effects of the gradually increasing 

 percentage of combined acid. The third memoir is by 

 the Editor and Dr. Painter, on the influence of certain 

 therapeutic and toxic agents on the amylotic action of 

 saliva. The substances selected for study, besides those 

 noted for therapeutic or toxic power, were also those 

 possessed of antiseptic properties. Mercuric chloride, 

 which acts so powerfully as a germicide, acts even more 

 energetically on the organised ferment of saliva. It is 

 interesting to find that air, oxygen, and carbonic acid all 

 stimulate the amylotic ferment, and this approximately in 

 proportion to the extent in which they are present in the 

 natural secretion ; while of the reducing gases, hydrogen 

 retards and hydrogen sulphate stimulates. In a fourth 

 nremoir, by the Editor and S. E. Allen, the subject is the 

 influence of various inorganic and alkaloid salts on 

 the proteolytic action of pepsin-hydrochloric acid. In 

 this the comparative influence on gastric digestion of 

 various metallic salts well known as poisons or therapeutic 

 agents has been studied, and some experiments on some 

 alkaloid salts are added. The subject of the influence 

 of temperature on the relative amylotic action of saliva 

 and the diastase of malt is treated of by the Editor 

 and Dr. W. E. Martin. The influence of various 

 therapeutic and toxic substances on the proteolytic 

 action of the pancreatic ferment, and on the influence 

 of bile, bile salts, and bile acids on amylotic and proteo- 

 lytic action are investigated in two memoirs by the Editor 

 and Dr. Cummins. There is a very interesting, and, from 

 a medico-legal point of view, important memoir on the 

 absorption of arsenic by the brain tissues, by the Editor 

 and Dr. Herbert E. Smith. Two memoirs on the influence 

 of potassium and ammonium bromides, and on cincho- 

 nidine sulphate on metabolism, are by the Editor and Dr. 

 W. Culbert, and the Editor and Dr. Henry Whitehouse ; 

 while a memoir on the post-niorton formation of sugar in 

 the liver in the presence of peptones, by the Editor and 

 Dr. Alex. Lambert, concludes a volume which in many 

 ways reflects great credit on the work done at Yale 

 College, and shows an intimate knowledge of the labours 

 in the same direction of the authors' fellow-workmen in 

 Europe. 



Catalogue of the Lizards in the British Museum {Natural 

 History). 2nd Edition. By George Albert Boulenger. 

 Vol. II. 



The rapid progress made with this important Catalogue 

 shows an amount of energy on which the authorities of 



the British Museum and herpetologists generally may be 

 congratulated. The first volume appeared early in 1885, 

 and was noticed in N.'VTURE for IVIay 21 (vol. xxxii. p. 

 49) ; the second volume was issued before the conclusion 

 of the year. 



This volume contains the following families of lizards : 

 Iguanida?, with 293 species ; Xenosaurida;, with i ; 

 Zonurida:, 14; Anguid<E, 44; Anniellidae, 2; Heloder- 

 matidffi, 3 ; Varanida;, 27 ; Xantusiida;, 4 ; Teiida;, 108 ; 

 and AmphisbiBnidiE, 65 ; or a total of 561 species, dis- 

 tributed amongst 1 1 5 genera. The number of species is 

 consequently rather greater than in the first volume, 

 which contained descriptions of 490. In the present as 

 in the preceding volume several genera proposed by 

 previous writers are united into larger generic groups : 

 thus in the Varanida only one genus, Varanus, is recog- 

 nised in place of the seven into which the family was 

 divided in Dr. Gray's Catalogue of 1845. I Five new 

 genera are proposed — three in the Iguanidfe and two in 

 the Teiida;. The construction of one of the names pro- 

 posed, Enyalioides, is, however, unfortunate, as the 

 termination, that of an adjective, is objected to by many 

 naturalists, and there is consequently the risk of another 

 term being proposed. 



Nearly all the Iguanida; and all the Teiidffi are 

 American, and as these two families contain between 

 them 401 species out of the total number described in the 

 volume there is a great preponderance of types peculiar 

 to the New World. Two of the exceptions to the pre- 

 vailing American distribution in the case of the Iguanidae, 

 the genera Chalarodon and Hoplurus, are peculiar to 

 Madagascar, although no species of the family has been 

 discovered in Africa. 



The lithographic plates attached to both this and the 

 previous volume are excellent, and the figures of lizards, 

 even if not quite so life-like as the highly artistic drawings 

 of the late Mr. Ford, are far superior to the illustrations 

 usually found in works on Reptilia. W. T. B. 



Pliysikalische Krystallographie und Einleitung in die 

 krystallographische Kenntniss der luichtigeren Sub- 

 stanzen. Von P. Groth. 2nd Edition. (Leipzig : 

 Wilhelm Engelmann, 1885.) 



This is the most satisfactory work of its kind which has 

 been published in any language. In a very simple way 

 the chemist is made to comprehend the mysteries of 

 geometrical crystallography, the physicist is taught how 

 intimately optical and other physical characters are related 

 to crystalline form, while to the microscopical petro- 

 grapher is presented a careful explanation of the 

 principles upon which all his determinations must be 

 based. We are glad to see that in this edition the simple 

 notation of the late Prof Miller, of Cambridge, reigns 

 almost supreme ; doubtless, it will soon succeed in driving 

 its unpronounceable rivals completely from the field, to 

 the relief of every student. Stereographic projection too 

 takes a very prominent place. In the present edition the 

 work has been increased by 1 80 pages, most of which are 

 given to the chapter descriptive of the instruments : there 

 are as many as 631 woodcuts. We wish this edition all 

 the success it deserves. 



The Rudiments of Mineralogy. By Alexander Ramsay, 

 F.G.S., S:c. Third Edition. (London : Crosby Lock- 

 wood & Co., 1885.) 



Mr. R.A.MSAY is far from being a master of his subject. 

 We cannot imagine what advantage the elementary 

 student, for whom the book is intended, can deri\'e from 

 information as to the specific gravity of each species 

 relative to hydrogen : in the case of native silver, for 

 example, he is told that the specific gravity ranges 

 from 115,123 to 117,369! And in any case what is 



