摘要:

SummaryThe present review of the literature of mass physiology is limited to the years just previous to 1933, and for approximate completeness must be read in connection with an earlier and more extensive survey (Allee, 1931). Analysis of the reactions leading to the formation of aggregations in nature or in the laboratory has scarcely proceeded beyond the recognition hat much of such behaviour is innate. There is, however, recent evidence that a part of the schooling behaviour of the fishAmeiurusis acquired rather than inherited.Once formed, aggregations of aquatic organisms condition the medium surrounding them by the addition of secretions and excretions, the nature and the biological effects of which form one of the important problems of mass physiology.It is easy to demonstrate that overcrowding lessens the rate of growth of organisms. More recently evidence has been accumulating that undercrowding frequently has the same effect. Evidence is presented on this point in such widely different animals as mealworms, fishes and mice. Similarly, with population growth the harmful effects of undercrowding have recently been found for protozoans, crustaceans and beetles, as well as the ill effects of overcrowding.The results from aggregation upon rate of oxygen consumption varies with different animals, and even with the same animals at different times of the year. With goldfishes, those in small groups use less oxygen per individual if grouped than when isolated; with the more closely schoolingAmeiurusopposite results are reported. Outside the breeding season, the brittle starfishOphiodermaconsumes less oxygen per individual if grouped; this relationship does not necessarily hold during the breeding season.Groups of animals are able to afford protection to their members if exposed to toxic conditions produced either by the absence of accustomed salts, as the marine flatwormProcerodesdoes when placed in fresh water, or by the presence of toxic substances such as colloidal silver. The amount of protection furnished has been measured for certain cases, and the protective mechanisms are discussed.The polarity of the seaweedFucuscan be determined by the position of a given egg with reference to a group of other eggs of the same or of a different species. Such plasticity might be expected from plants more readily than from animals. With animals, Uvarov's phase theory of locusts has been experimentally demonstrated to hold for the South AfricanLocustana pardalina. The transition from parthenogenetic to sexual reproduction in certain cladocerans has again been demonstrated to result from crowding, and considerable progress has been made in the analysis of the relative importance of the presence of metabolic products and of nutrition in the control of sex in these animals.The effects of numbers present upon the rate of learning differs with different animals and even in the same animals with different problems. Thus fishes learn to run a simple maze more rapidly if in groups than if isolated, but they learn less readily to jump for a bit of worm held just above the water level. Cockroaches also learn to run a simple maze more slowly if more than one is present in the maze at the same time.Groups of birds show a fairly definite flock organisation, which may or may not be related to active leadership of the flock.The whole range of mass physiology has been presented with the thought that it forms a large part of the background for social life.

ISSN:1464-7931    

DOI:10.1111/j.1469-185X.1934.tb00872.x

出版商:Blackwell Publishing Ltd    

年代:1934

数据来源: WILEY

摘要:

Summary1. Ultra‐violet light produces a strong bluish white fluorescence in the eyes of all vertebrate animals hitherto investigated (mammals, birds, reptiles, and amphibians). The lenses shine most strongly but to varying extents, those of young animals glowing less than the lenses of older individuals. It appears that twilight animals have less strongly fluorescent lenses than diurnal forms. The transparency of the component parts of the eye decreases in proportion to the amount of fluorescence, without, however, being completely abolished. Vertebrates can barely see wave lengths shorter than 300 mμ, and many lenses completely absorb light below 313 mμ (frog, cat). Ultra‐violet images on the human retina may be suppressed by fluorescence from the lens. The brightness of ultra‐violet light is small, and for this reason it does not disturb us in daylight. Inflammation of the front parts of the eye may result from the shorter ultra‐violet rays of the sun. Normally the retina and the floor of the eye are protected by the strong absorption of these rays in the lens. Nevertheless, strong ultra‐violet light may injure the retina.2. In minnows a movement of the retinal pigment occurs even in the long wave ultra‐violet, accompanied by a migration of rods and cones. In pure ultra‐violet the cones are situated on the limiting membrane, as they are in visible light. Fluorescent light produces the same effect, although less strongly than ultra‐violet.3. Fluorescence likewise results in the eyes of insects wherever ultra‐violet light falls on colourless tissues. The colourless chitin over the eye shines strongly when it is sufficiently thick. Nevertheless, ultra‐violet light cannot be demonstrated at the back of the eye. The tracheal tapetum of many eyes shines noticeably, and by the disappearance of the glow it can be recognised that this eye pigment too migrates in ultra‐violet light. In the case of sensitive twilight butterflies fluorescent light can produce this movement of pigment, but in diurnal forms ultra‐violet radiation alone is effective.4. Bertholf showed that bees andDrosophilaare attracted to the ultra‐violet spectrum when they are exposed simultaneously to a certain intensity of white light. The strongest maximum is at 366 mμ and is 4.5–5.5 times as strong as that in the green region.Drosophilahas 3 maxima, one at 487 mμ, the highest at 366 mμ and a weak maximum at 254 mμ. The bee has 2 maxima only, at 555 mμ and 366 mμ. The bees' spectrum extends further into the red and ends in the short wave region at 300 mμ. TheDrosophilaspectrum extends beyond 300 mμ but appears to be curtailed in the red.5.Daphniaturns on to its back in long wave ultra‐violet coming from below, just as it does in visible light, even when exposed at the same time to fluorescent light from above. This demonstrates the stronger effect of ultra‐violet light on the animal.6. Planarians move away from long wave ultra‐violet just as they do from visible light. Fluorescent light has a weaker action. A physiological equilibrium is attained with a visible light of 200–300 lux opposed to 0.07 B.‐R. units of ultra‐violet. Left‐eyed planarians move away from ultra‐violet light to the right, right‐eyed animals to the left, while those with both eyes move away along a very narrow track. Lighted from above the left‐eyed animals circle to the right, those with right eyes the left. The circles are smaller in strong than in weak lig

ISSN:1464-7931    

DOI:10.1111/j.1469-185X.1934.tb00873.x

出版商:Blackwell Publishing Ltd    

年代:1934

数据来源: WILEY

摘要:

Summary1. In the preceding pages the application of the concept of heterogony to the chemical changes in growing Metazoa has been discussed.2. A number of concrete examples have been brought forward which seem to indicate a uniformity of chemical heterogony in widely different organisms.3. Hence it is suggested that there exists a fundamental chemical ground‐plan of animal growth, capable of very varying expression in space‐t

ISSN:1464-7931    

DOI:10.1111/j.1469-185X.1934.tb00874.x

出版商:Blackwell Publishing Ltd    

年代:1934

数据来源: WILEY

摘要:

Résumé1. Les néphrons des Vertébrés peuvent se classer en néphrons ouverts et néphrons fermés, selon qu'ils présentent ou non une communication directe avec la cavité péritonéale, par l'intermédiaire d'un néphrostome.2. Le glomus et le glomérule sont des appareils filtrants laissant passer, non seulement ies substances diffusibles, mais encore les colloïdes de haute dispersion.3. Le segment à brosse jouit de propriétés résorbantes, s'exerçant aux dépens de substances filtrant par le glomérule. Cette propriété est nettement mise en évidence par l'injection de substances colloïdales très disperses qui apparaissent dans les cellules de ce segment lorsque le glomérule fonctionne normalement et qui n'y pénètrent plus lorsque la fonction glomérulaire est expérimentalement supprimée.4. Le segment à brosse jouit d'un pouvoir athrocytaire, caractérisé par l'absorption, la concentration et la rétention sous forme granulaire detousles colloïdes portés au contact du pôle apical de ses cellules. L'athrocytose de substances colloïdales de dispersion moyenne ou faible ne peut évidemment s'observer que dans les néphrons ouverts, ou encore dans les néphrons fermés dont la perméabilité glomérulaire a été pathologiquement augmentée (néphrose lipoïdique).5. Le segment à brosse est phagocytaire, par son pôle apical (absorption de mélanine et de cinabre).6. Il existe, dans le segment à brosse, un gradient de perméabilité apicale des cellules. Cette perméabilité est minimale au début du segment et augmente progressivement en sens distal. L'existence de ce gradient est démontrée par le décalage en sens distal, du point d'athrocytose maximale pour des colloïdes de dispersion diverse; ce décalage est d'autant plus marqué que le degré de dispersion est plus faible.7. L'athrocytose de substances colloïdales diffère de la résorption des substances diffusibles en ce qu'elle s'accompagne d'une rétention prolongée des substances résorbées.8. Le segment à brosse jouit en outre d'un pouvoir émonctoire, grâce auquel des substances de déchet peuvent être directement éliminées au dehors, sans filtration préalable par le glomérule. Cette fonction émonctoire, évidente dans les néphrons aglomérulaires, peut être démontrée expérimentalement par suppression de la fonction glomérulaire chez l'Anoure: l'élimination de l'acide urique continue à se faire dans ces conditions.9. Le segment à bâtonnets possède un pouvoir de résorption d'eau, démontré par les images obtenues après injection d'acide urique ou de nitrate d'urane.10. Le ntphron primitif du Vertébré est un néphron ouvert. L'apparition du glomérule s'accompagne de la perte de la communication péritonéale.Summary1. Vertebrate nephrons can be classified into open and closed according as they have or have not direct communication with the peritoneal cavity through the intermediary of a nephrostome.2. The glomus and the glomerulus are filters which allow not only diffusible substances to pass but also highly dispersed colloids.3. The “segment à brosse” [proximal convoluted tubule] possesses a resorbant function with respect to substances filtering through the glomerulus. The property in question can be clearly demonstrated by the injection of highly dispersed colloids, which reappear in the cells of this segment when the glomerulus functions normally, but no longer penetrate into them when the glomerular function is experimentally inhibited.4. The “segment à brosse” has an athrocytary function, characterised by the absorption, concentration, and retention in granular form, of all colloids brought into contact with the apical pole of these cells. Athrocytosis of colloids of medium or feeble dispersion can, of course, only be seen in the case of open nephrons, or of closed nephrons the glomerular permeability of which has been pathologically augmented.5. The “segment à brosse” acts phagocytically through its apical pole, absorbing melanin and cinnabar.6. There exists a gradient in the apical permeability of the cells in the “segment à brosse.” This permeability is at a minimum at the beginning of the segment and increases progressively in the distal direction. The existence of this gradient is shown by a shift in the distal direction of the point of maximal athrocytosis for colloids of varying dispersions: the shift is the greater the lower the degree of dispersion of the colloid.7. Athrocytosis of colloids differs from the resorption of diffusible substances in that it is accompanied by a prolonged retention of the substances resorbed.8. The “segment à brosse” also possesses an excretory function by which waste matters can be directly excreted without previous filtration through the glomerulus. This excretory function, clearly evident in nephrons lacking glomeruli, can be demonstrated experimentally by the suppression of the glomerular function in Anura. Under these circumstances uric acid continues to be excreted.9. The “segment à bltonnets” [distal convoluted tubule] has the capacity of resorbing water. This can be demonstrated by the injection of uric acid or of uranium nitrate.10. Th

ISSN:1464-7931    

DOI:10.1111/j.1469-185X.1934.tb00875.x

出版商:Blackwell Publishing Ltd    

年代:1934

数据来源: WILEY

ISSN:1464-7931    

DOI:10.1111/j.1469-185X.1934.tb00876.x

出版商:Blackwell Publishing Ltd    

年代:1934

数据来源: WILEY