August io, i905_ 



NA TURE 



357 



I'his r^iises the cjuestion lie; to the part played by the 

 nucleus of a cell in its respiratory processes. 



Is the source of muscular energy to be sought in oxida- 

 tion or cleavage processes in tissues? In some animals 

 there is not a direct relation between the muscular work 

 and oxygen consumed, though there is to heat production. 

 Bunge, on this ground, thought that the intestinal para- 

 sites of warm-blooded animals must have their oxygen at 

 a minimum. In the intestinal contents there is no estim- 

 able oxygen ; there active reduction processes go on. 

 Entozoa might get o.xygen from O, diffusing from blood- 

 vessels. 



Bunge found that intestinal worms of the cat and pike 

 can live in an alkaline solution of common salt, free from 

 gases, under Hg, for four to six days. They made active 

 movements, and gave off much CO,. 



.\scaris Iiimbricoides from the intestine of the pig lived 

 four to six days in i per cent, boiled NaCI solution. 

 It made little difference whether oxygen or hydrogen was 

 passed through the fluid. They lived seven to nine days 

 if fluid was saturated with carbon dioxide, so that they 

 have accommodated themselves to high percentages of 

 carbon dioxide. 



They give off to the fluid valerianic acid, an acid with 

 a characteristic butyric acid odour. These worms contain f 

 a very large quantity of glycogen, the dry body yielding 

 20 per cent, to 34 per cent, of this carbohydrate. 



too grams Ascaris, placed in boiled normal saline solu- 

 tion, used per day — 



0-7 gram glycogen, 



01 ,, sugar. 



No fat: 

 and yielded — 



04 gram CO, 



0-3 valerianic acid. 



It would seem that glycogen had split into CO,, and 

 valerianic acid — 



4C„H,„0,; = 9COo + 3C3H,„0.j + 9H., 

 720 = 396 -r 306 + iS. 



Is it a genuine fermentation? 



Weinland found that he could express by Buchner's 

 method a substance, "zymase," which could split glycogen 

 into CO, and valerianic acict. 



Turning now to respiration in invertebrate animals, and 

 dealing first with those which live in water, let us see 

 some of the contrivances by which this end is achieved. 

 The mechanisms are but means to an end. The ultimate 

 union of oxygen, and the discharge of carbon dioxide with 

 the liberation of energy, occur in the protoplasm of the 

 cell itself. 



There are two distinct processes, and it may be that 

 the oxygen is introduced by one portal and the carbon 

 dioxide got rid of by another, or it may be that one portal 

 may do for both processes — the letting in of o.xygen and 

 the giving off of carbon dioxide. 



.\lthough the principle itself is simple, the variety of 

 mechanisms adopted by nature to secure this double func- 

 tion is remarkable. Let us glance at some of the 

 mechanisms proceeding from the simple to the complex, 

 and first with regard to those animals that live in water. 



Consider the oceanic fauna. It is immense both from 

 the point of view of number and variety. Save insects 

 and certain groups of molluscs, all invertebrates are 

 aquatic. Amongst vertebrates, fishes have aquatic respira- 

 tion, and some mammals, e.g. cetaceans or whales, have 

 water as their sphere of existence, though they depend on 

 the air for their respiratory o.xygen. 



The evolution from an aquatic to an aerial mode of 

 existence can be traced in the animal kingdom, and may 

 even be seen within limits in the history of certain species. 



Every living cell, animal or vegetable, requires for its 

 continued existence a supply of oxygen, and every living 

 cell exhales carbon dioxide. The exchange of these two 

 gases between the fluids of the body and the outer medium 

 is the process of respiration. The simplest form of 

 respiratory exchange occurs where there is no specially 

 differentiated organ or mechanism for this purpose, so- 

 called diffuse respiration. The whole surface of the 



NO. 1867, VOL. 72] 



organism in a watery medium may be concerned in this 

 respiratory exchange. This is only possible, however, so 

 long as the boundary surface, skin, or otherwise is 

 permeable to gases, and no great respiratory exchanges 

 are necessary. 



Before showing you some lantern slides, I should like 

 to point out how one process is made to aid another. 



Motion associated with respiratory processes. 



Ciliary motion with respiration and Ihe capture of prey 

 for food. 



The old idea of one function for an organ is exploded. 

 One speaks of one man one vote. One man one value. 

 It is not really so. 



With Shelley we may say — 



" Nothing in ihis world is single ; 

 All things, by a law Divine, 

 In each other's being mingle.'" 



As regards the surfaces for these respiratory e.xchanges 

 for diffuse respiration, it may take place through the inner 

 surface of the body cavity of coelenterates, the under 

 surface of the bell of a medusa, the tentacles of an echinus, 

 the respiratory tree. at the hind gut of the sea cucumber, 

 or the intestine of the young of the dragon fly, or by the 

 intestinal mucous membrane of the mites which have no 

 lungs or other directly respiratory organ. In the higher 

 animals we have trachea', gills and lungs. 



In some animals, the respiratory mechanism is closely 

 related to the motor apparatus, as in some Crustacea. 

 In some mollusca the nutritive and respiratorv mechanisms 

 are closely related. In the highest of all there is central 

 apparatus— gills or lungs— for the respiratorv exchange 

 between the blood and the air, and a circulatory apparatus 

 for carrying the blood to and from the respiratorv organs. 

 The adaptivity of insects to varied conditions of oxygen 

 supply is marvellous. 



Before showing some classical experiments and illus- 

 trating the principles already laid down, I should like again 

 to direct your attention to the association of several 

 processes with respiratory mechanisms. 



[The lecture was illustrated by means of lantern slides, 

 showing the respiratory mechanisms from the lowest to 

 the highest animals, and also by a number of experiments 

 dealing with the chemical exchanges in the process of 

 respiration. Lastly, the classical experiment of John 

 Hunter, on the pneumaticity of the bones of birds, was 

 shown in the duck. .\ candle flame was extinguished 

 when held in front of the divided trachea, when air was 

 blown into the divided humerus bone of the wing.] 



UMVERSITY .iND EDUCATIONAL 

 INTELLIGENCE. 



On June 27, Amherst College, Massachusetts, conferred 

 the degree of M..A. upon .Mr. Lundin, of Messrs. Alvan 

 Clark and Sons, the following being President Harris's 

 characterisation : — " Carl .Axel Robert Lundin : Scien- 

 tific expert in cutting and fashioning glasses of great 

 telescopes. He has done important work on the large 

 objectives of Russia, of the Lick and Verkes observatories, 

 and lately on the 18-inch objective of the .\mherst College 

 Observatory, which is wholly his work. In 1854 .Amherst 

 conferred the degree of Master of Arts on Alvan Clark, 

 who had built our first telescope. The same degree, for a 

 similar service, is conferred on his successor, who has 

 kept pace with the progress of astronomical science." 



.An interesting inquiry as to the representation of science 

 in the principal public libraries of Paris is being made by 

 the Revue Scientifique, and the results are published 

 week by week, from July i onwards, in the form of letters 

 and opinions from the principal librarians and professors 

 of science in France. The opinion is generally expressed 

 that an unsatisfactory state of affairs exists in libraries 

 such, for instance, as the Biblioth^que nationale and the 

 library of the University of Paris owing to the fact 

 that the librarians are almost exclusively graduates in 

 arts and letters, and ignorant of the requirements of men 

 of science. It thus happen.s that, the available funds 



