Abstract
LONDON Royal Society, February 22. A. S. PABKES and M. HILL: Effect of absence of light on the breeding season of the ferret. Bissonnette's discovery that additional illumination would induce oestrus in anoastrous ferrets has naturally led to speculation s to what controls the onset of the breeding season in the normal ferret. An obvious interpretation of Bissonnette's results was that the beginning of the breeding season of the normal female ferret in April is due to the increasing duration of daylight. This hypothesis was put to experimental test by keeping ferrets in darkness from the latter part of anostrus onwards. From the results it is concluded that while additional light will induce oestrus in ancestrous animals, the onset of the breeding season in the spring is not dependent on the increasing length of daylight. L. E. S. EASTHAM: Metachronial rhythms and gill movements in relation to water flow in the nymph ofCcenis horaria (Ephemeroptera). By means of the oscillatory movements of four pairs of gills, the nymph produces a flow of water across the body from one side to the other, the current being reversible. The gills rise and fall in periodic motion, and in so doing they traverse an elliptical path and, by a pivoting movement, move at an angle with their own path of motion. The metachronial rhythm in the movements of the gills along each side of the body is from before backwards, but the gills of one side in motion are always out of phase with those of the other. A transverse rhythm therefore exists across each pair of gills, which rhythm is in the direction of the water flow across the body. It is reversed when the direction of the water current is reversed. Reversal of flow is associated with changes in the method of pivoting of the gills; their manner of overlapping as members of pairs; the direction of the transverse rhythm over the gills. F. J. W. ROUGHTON: The kinetics of haemoglobin (4-7). The methods of Hartridge and Roughton for the study of the velocity of rapid reactions were first applied by them to the reaction between haemoglobin and oxygen. The present papers extend the work to the ‘sister’ reactions of haemoglobin with carbon monoxide. Velocity equations have been arrived at for (i) the combination of carbon monoxide with reduced haemoglobin, CO+Hb-COHb; (ii) both phases of the reversible reaction, CO+O-Hb; ±O2 + COHb. The results do not accord theoretically with a chemical mechanism of the type Hbn + nCO; ±Hbw (CO)n, but can in part be interpreted by Adair's intermediate compound hypothesis, according to which the reaction of oxygen or carbon monoxide with haemoglobin takes place in successive stages. New possibilities are, however, brought to light, notably when trying to explain the paradoxical observations that pll is almost without effect upon either phase of the reversible reaction CO+O2Hb; ± O2 + COHb.
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Societies and Academies. Nature 133, 338–340 (1934). https://doi.org/10.1038/133338a0
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DOI: https://doi.org/10.1038/133338a0