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constant diet containing as few chlorides as possible. Following out a similar experiment on man, it was found that chloroform narcosis here also produced an increase in the urinary chlorides.

Chloral was next investigated, and it was found to have no such effect in producing an increase in the chlorides of the urine; Mering has previously shown that this substance leaves the body as urochloralic acid, and does not part with its chlorine. Similar investigations with carbon tetrachloride, methyl chloride, and ethyl dichloracetate also gave negative results, but ethyl trichloracetate, on the other hand, produced a very decided increase in the output of chlorides. W. D. H.

Formation of Xanthocreatinine in the Organism. By A. MONARI (Gazzetta, 16, 538-543).-In the course of investigations on the changes produced by fatigue in the chemical composition of muscle, it was observed that the quantity of creatinine was one-third to one-half greater than that of creatine, and that the compound of creatinine with zinc chloride was precipitated in pale-yellow, acicular crystals. In the course of working up an extract of flesh, a yellow flocculent mass was obtained soluble in water and alcohol, from which it may be recrystallised. This substance was shown by analysis and by its physical and physiological properties to be identical with the xanthocreatinine isolated by Gautier.

The same substance was also extracted, together with creatinine, from the urine of soldiers after a march of several hours. Considerable difficulty was experienced in the complete separation of the xanthocreatinine from creatine. V. H. V.

Invertebrate Chromatology. By C. A. MACMUNN (Proc. Physiol. Soc., 1887, 11-12).-Chlorophyll is present in nine specimens of seawater sponge in addition to the fresh water sponge, the presence of chlorophyll in which was shown by Ray Lankester. A histohæmatin soluble in glycerol was found in seven species; in some reddish sponges this is replaced by tetronerythrin or allied pigments. In most sponges, various lipochromes are present.

Hæmatoporphyrin occurs in all parts of the body of the mollusc Solecurtus strigillatus, except where it is attached to the shell. It is curiously distributed in the epidermis, being laid down at the margins of the cells, which are serrated, and reminding one of pavement epithelium stained with silver nitrate.

In Anthea cereus, chlorophyll is present, but in this case is due to the presence of symbiotic algae. In Flustra foliacea, chlorophyll is present in the "brown bodies," which Moseley says are due to the atrophy of the zooids. As these "brown bodies" contain diatoms, &c., eaten by the zooid, it is possible that chlorophyll may in this case be derived from food products. Its spectrum, however, resembles that of enterochlorophyll. W. D. H.

Analysis of Nitrogenous Metabolites in Fæces. By A. STUTZER (Zeit. physiol. Chem., 11, 361-364).-The author has previously described (Abstr., 1886, 377) a method of separating the nitrogenous

constituents of fæces due to metabolism from those which are not, by means of artificial gastric juice, or better still by the successive action of gastric and pancreatic ferments. Pfeiffer has stated that the fæces must be used in the fresh, not in a dried condition, as the process of drying converts some of the nitrogenous constituents of the fæces into such a condition as to be indigestible. The fæces used in Pfeiffer's work had, however, been under alcohol for two years, and therefore it was deemed advisable to repeat the experiment. The fæces of the cow and horse were used, and the result of nitrogen estimations confirms the accuracy of Peiffer's statement as is shown by the following numbers :

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Proteïds of Cerebrospinal Fluid. By W. D. HALLIBURTON (Proc. Physiol. Soc., 1887, 14).-A few specimens of fluids obtained from meningocoles and from cases of chronic hydrocephalus were examined. It was found that all the proteïds were precipitable by saturation with magnesium sulphate. Serum albumin was therefore absent. The precipitate was redissolved and found to consist of a small quantity of serum globulin, but the greater part consisted of proto-albumose. In one case, a variety of albumose was present, which was not precipitable by magnesium sulphate or sodium chloride (deutero-albumose). In cases of acute hydrocephalus, the total quantity of proteïds in the cerebrospinal fluid was greater than normal, and the fluid contained serum albumin as well as serum globulin and albumose. The question as to whether a proteolytic ferment exists in the fluid has not as yet been investigated. A number of specimens of hydrocele, pericardial, peritoneal and pleuritic fluids were also examined for albumoses, but with negative results. Several specimens of human blood, and the blood of other mammalian animals were also examined, but no albumose was found in any of them.

This peculiarity of the proteïds of cerebrospinal fluid, together with the previously known facts of the existence of a substance in it which reduces alkaline solutions of cupric hydrate, and of the excess of potassium over sodium salts in the fluid, shows that effusions into the cerebrospinal cavity differ considerably from the other socalled serous effusions. W. D. H.

Therapeutic Action of Colchicine. By A. MAIRET and CoмBEMALE (Compt. rend., 104, 515-517).-Experiments on men, dogs, and cats show that colchicine acts either as a diuretic or a purgative

according to the dose administered, and acts by irritating the kidneys and digestive canal. The effects are the same whether the drug is administered hypodermically or by ingestion, but the action is more rapid in the former case, and the effects are produced by smaller doses. Man is three times more sensitive to its action than are cats and dogs. A dose of 2 to 3 mgrms. is sufficient to produce the diuretic, and 5 mgrms. to produce the purgative action. Colchicine increases the excretions and produces congestion at the articulations and in the bony cartilage. Its tendency to accumulate in the organism, and its great toxic power, make it essential to use the greatest care in administering it. C. H. B.

Chemistry of Vegetable Physiology and Agriculture.

Changes Induced in Water by the Development of Bacteria. By T. LEONE (Gazzetta, 16, 505-511).-The author has already demonstrated that the number of micro-organisms, in a typically pure water, such as the Maugfall near Munich, although at first small, yet on standing gradually increase to a maximum, and afterwards rapidly decrease. The development of bacteria induces certain chemical changes in the water; thus the quantity of oxidisable organic matter gradually decreases, whilst the proportion of ammonia increases to a maximum, and then decreases owing to its oxidation into nitrites and nitrates; on this account, the time which elapses between the taking of a sample and its analysis is an important factor. The consequent changes are divisible roughly into two distinct periods: the first, in which the organic matter is decomposed with production of ammonia; and the second, in which this is subsequently oxidised. It is further shown, on the other hand, that certain micro-organisms seem to act as reducing agents, reconverting the nitrates into ammonia, and even the same organisms, according to the conditions, may have either an oxidising or a reducing function. In the first phase, when the nutritive matter is readily oxidisable and assimilated, the microorganisms thrive at its expense, the process of nitrification being materially assisted by atmospheric oxygen; in the second phase, on the other hand, the necessary oxygen is derived from the nitrates; thus a change, seemingly of reduction, is induced. V. H. V.

Formation of Albumin in Plants. By A. EMMERLING (Landw. Versuchs-Stat., 1887, 1-180).-This long paper is a report of a series of experiments made by the author in order to determine the locality in which, and the mode by which, vegetable albumin is formed: they are a continuation of previous experiments of his own, and a kind of test of those made by Kellner, Schultze, Hornberger, and others, abstracts of whose researches will be found in this Journal, 1879, 819; 1880, 279, 493, 731; 1883, 491; 1885, 1087.

Observers have adopted two hypotheses to account for the phenomena of the production of amido-compounds in plants. One that they are formed synthetically in the plant from inorganic nitrogenous matter and organic substances brought into contact with it; the second, that they are formed from the decomposition of albumin already existing in the plant.

Growing plants are rich in amido-acids, the quantity diminishes as the plants grow older, and young cells cease to be produced, the amides being specially their nutriment. Schultze (Abstr., 1883, 493) thinks that there is a constant process of decomposition and reformation. Hornberger, in his studies on the growth of the maize plant (Abstr., 1883. 491), and on that of Sinapis alba (Abstr., 1885, 1087) has thrown very great light on the subject; he is of the opinion that amido-compounds are formed according to the first hypothesis, but does not indicate the locality of their production.

The results of the author's experiments are given in tables which cover 46 pages. The plants used were the common bean, and the estimations comprised-total dry substance, total nitrogen, nitrogenous combinations soluble in aqueous potash, nitrogen existing as legumin, albumin, ammonia, amido-acids, amides, carbamides, and nitrates respectively, sulphur as sulphuric acid, and in organic combination.

There is an intimate and striking connection between the development of the leaves and the fruit of plants; when the leaf is growing, the production of nutrient matter is very active, but it is consumed by the leaf itself. When it has ceased growing, the same active production continues, but it is for the benefit of the seed or fruit, which only develops when the leaf is fully formed; the author believes that the leaf is the principal centre of albumin formation from whence it is diffused throughout the plant, the roots and stems playing a subordinate part in the process. In all parts of the plant, amidoacids are found, and it would seem that there are several centres of production.

The formation of new cellular matter in the first case is at the cost of the nitrogen stored in the seeds, and as the plant grows the quantity contained in the stem and roots sensibly diminishes.

The results of researches hitherto made are not decisive, however, although the author believes that the weight of probability is in favour of the synthesis of amido-compounds from inorganic and organic nitrogenous matter; he considers the difficulties of the alternate hypothesis too great, as it requires a regressive metamorphosis in presence of a most active production of the very matter which is being decomposed. The question, however, must still be considered an open one, as in recent experiments of Borodin and Schultze they observed that on many occasions cut plants placed in water for some time produced considerable quantities of asparagine and other amido-compounds which arise from the decomposition of albumin. J. F.

American Barley. By C. RICHARDSON (Amer. Chem. J., 9, 16— 22). Märcker found that the finest grain contained not more than 8 per cent. of albuminoïds, and consisted of at least 80 per cent. mealy kernels. Of 12 typical specimens of the Canadian crop, none

were below 9 per cent. of albuminoïds, the average being 9.83, and only 6 contained 60 per cent. of kernels mealy or half mealy in structure. The average amount of albuminoïds in the barley of the United States, 11:50 per cent., is still higher. The average of 127 specimens from all parts of the world is given by Koenig as 11.14 per cent. Winter grown barley contains less albuminoïds than springgrown, namely, 10-05 as against 11:42 per cent. H. B.

By A. GIRARD

Destruction of the Nematoïds of Beetroot. (Compt. rend., 104, 585—587).-When the nematoïds have not been long established and the area infected is limited, carbon bisulphide is an efficacious remedy, but must be applied in considerable quantity. Very satisfactory results were obtained by injecting it into the soil at a depth of 0.25 metre in the proportion of 300 grams per metre. Potassium thiocarbonate is of very little value as a remedy.

C. H. B.

Direct Absorption of Free Nitrogen from the Atmosphere by Vegetable Soils which are Supporting Vegetation. By BERTHELOT (Compt. rend., 104, 625-630).-The experiments were made with soils in which Amarantus pyramidalis was being grown. The nitrogen in the soil and in the roots of the plants were estimated at the outset, and the nitrogen existing in the rain-water and the ammonia in the atmosphere during the course of the experiments were also determined. The nitrogen in the water which drained from the soil was estimated, and at the close of the experiments the nitrogen existing in the plants and in the soil was determined. In all cases there was a very decided gain of nitrogen, which could only have been derived from the gaseous nitrogen of the atmosphere.

The increase of nitrogen whilst the soil is supporting vegetation is less than in the case of the same soil on which nothing is being grown. The plants consume a considerable part of the nitrogen, and it would seem that the life of higher plants like that of higher animals causes an incessant loss of combined nitrogen. Further experiments are, however, required before this last conclusion can be regarded as placed beyond doubt.

C. H. B.

Incompatibility of Nitrates and Superphosphates. By A. ANDOUARD (Compt. rend., 104, 583-585).—Mixtures of nitrates with superphosphates very rapidly lose their nitric nitrogen in the form of nitrogen oxides, and therefore still more rapidly when exposed on the surface of the soil to direct solar radiation. At the same time, there is some loss of organic nitrogen, and if the manure also contains ammonium salts there is likewise a loss of ammoniacal nitrogen.

C. H. B.

VOL. LII.

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