PHYSIOLOGY. 



727 



ments and by the vibrations of the membrana 

 tympani compounded with them. 



Criticising the recent study of Argutinsky 

 on muscular work and nitrogeneous metab- 

 olism, according to which work done in 

 climbing a mountain and the heat produced are 

 the outcome of the breaking down of nitroge- 

 neous material, Dr. I. Munk comes to the con- 

 clusions that the climber's body was not in nitro- 

 geneous equilibrium even during rest, and that 

 the amount of carbohydrate taken by him is in- 

 sufficient to account for the heat production 

 during rest. Both these factors lead to an in- 

 creased nitrogeneous metabolism when extra 

 work is done, the energy required for the excess 

 of work being obtained from the breaking down 

 of proteids; hence no conclusions as to what 

 normally takes place can be drawn from Argu- 

 tinsky's experiments. It was further pointed 

 out that Oppenheim's experiments have shown 

 that dyspnoea leads to increased nitrogeneous 

 metabolism, and that hence dyspnoea may proba- 

 bly have played some part during the exertion 

 of excessive climbing. While he did not doubt 

 the accuracy of the experiments, the author did 

 not feel that the conclusions which Argutinsky 

 had drawn from them were justifiable. 



Vegetable Physiology. M. Victor Jodin 

 communicated to the French Academy of Sci- 

 ences in February " A Study of Chlorophyll, in 

 Connection with M. Regnard's Induction that 

 the ' Chlorophyll Function ' that is, the Property 

 of Decomposing Carbonic Acid is of a Purely 

 Chemical Order inherent to Chlorophyll, and con- 

 tinuing to act apart from the Physiological Con- 

 ditions." M. Jodin's experiments appear to 

 point to somewhat different results, and to show 

 that a general theory of chlorophyll, based on 

 well-established facts," has yet to be framed. 



Anna Bateson and Francis Darwin have ex- 

 perimented, to aid in illustrating the phenomena 

 -of growth, upon the effect of certain stimuli on 

 vegetable tissues. The experiments were made 

 with turgescent pith (of the sunflower and Jeru- 

 salem artichoke), which when relieved from the 

 unyielding external tissues that restrain it, at 

 once expands by becoming longer. The ordi- 

 nary course of growth of the pith in water was 

 first observed. It was found that in this what 

 was called a grand period takes place that is 

 to say, the growth is at first slow, then more 

 rapid, and ultimately becomes slow again, the 

 whole period taking perhaps twenty minutes. 

 This is precisely the series of changes which a 

 growing organ exhibits in the course of days in- 

 stead of minutes. If the water in the jar is 

 gradually warmed, the growth of the pith in- 

 creases in the most striking manner up to about 

 95, after which it usually becomes irregular 

 with some diminution ; and, just before a tem- 

 perature is reached which kills the tissues, a 

 rapid fall in the rate of growth sets in. The ad- 

 dition of alcohol to the water caused an increase 

 in the rate of growth for a short time. Similar 

 results were obtained with ether in small frac- 

 tions, administered in the form of vapor, but 

 "when the proportion of ether amounted to 3 

 per cent, of the atmosphere the pith was killed, 

 and showed no increase but a decrease in length. 

 Ammonia caused a temporary acceleration of 

 .growth. As a rule, acids produced no accelera- 



tion, but caused either retardation or flaccidity 

 and death ; but hydrocyanic acid had an action 

 comparable to that of alcohol. Extremely di- 

 lute solutions of quinine chloride acted poison- 

 ously, and produced a shortening of the tissues. 

 The most interesting fact established by these 

 experiments is the possibility of stimulating 

 turgescent tissues to increased elongation by 

 such reagents as alcohol, ether, and hydrocyanic 

 acid. 



The properties of pituri an alkaloid ex- 

 tracted from the leaves of an Australian shrub 

 which are taken by the natives as other races 

 take tobacco and of nicotine, have been studied 

 by J. N. Langley and W. Lee Dickinson. As a 

 rule, the physiological action of pituri was 

 found to be identical with that of nicotine. The 

 successive stages of nicotine poisoning are those 

 of excitation, spasms, quiescence, flaccidity, 

 paralysis of the central nervous system, and 

 paralysis of motor nerve endings. On the heart, 

 a small dose causes primary slowing of the beat, 

 and may cause a diastole lasting up to a minute ; 

 on recovery of the heart beat, the initiatory 

 fibers of the vagus are paralyzed ; except with a 

 small dose the primary inhibitory effect is slight, 

 and with a large dose it is absent. The heart beat 

 continues after very large doses. On the bodily 

 movements it causes clonic spasms and twitch- 

 ings of the muscles, and may cause convulsions 

 and ophisthotonos. Its effects on the pupil, 

 vaso-motor system, and other parts of the vital 

 economy, are also studied and compared with 

 those of pituri, and no obvious difference is 

 found between the two substances. 



The seeds of the Trichosanthes palmater are 

 inclosed in a rounded scarlet fruit and imbedded 

 in a green bitter pulp. The bitter principle has 

 been shown by Mr. D. Hooper to be a glucoside 

 differing from colocynthin, and he has named it 

 trichosanthin. The green coloring matter, when 

 freed from the trichosanthin and fatty matter, 

 yields a solution closely resembling a solution of 

 chlorophyll. It is green in thin, and red in 

 thick layers, and has a red fluorescence. The 

 spectrum, however, is different. The conclusions 

 to be derived from the study of it seem to be 

 that we have in the trichosanthes coloring mat- 

 ter a substance in which the "blue chlorophyll " 

 of Sorby or the " green chlorophyll " of Stokes 

 is replaced by some other substance easily de- 

 composed by reducing agents and acids. 



An investigation is in progress by Herr Kuy, 

 in Germany, of the relation between the branches 

 and roots of trees, the object of which is to de- 

 termine whether they are capable of exchanging 

 functions. A number of plants of Ampelopsis 

 and ivy w.ere planted, with both ends in the 

 ground, and in the next year, after the tops had 

 rooted, the arches were cut at their highest 

 point. In the first year two of the plants died, 

 but the others, twenty-six in number, grew vig- 

 orously and were alive in the spring of 1889, 

 four years afterward. To test the extent of the 

 inversion, slips were cut from the inverted 

 plants and planted in a green-house, some with 

 their natural and some with their artificial end 

 uppermost. The callus, from which the roots 

 spring, was formed at both ends, but more readi- 

 ly at the natural lower end, whether this was 

 above or below, in the experiment. The author, 



