 | 1862 - 498 Seiten
...peculiar result. It is the division and subdivision of the yolk, wholly or in part, which prodvices the germinal mass out of which the embryo is formed,...exposure to the light, by death of the animal, * " On the Cutaueous Pigmentary System of the Frog." ' Philosophical Transactions/ 1858. and by sudden section... | |
 | John Hughes Bennett - 1870 - 466 Seiten
...change of colour in the chameleon, in fishes, and numerous other animals. The black pigment molecules may be diffused throughout the cell or concentrated in a mass, and all kinds of and produce higher forms, must be attributed to a molecular force, operating in obedience to fixed... | |
 | Royal Society of Edinburgh - 1862 - 552 Seiten
...change of colour in the cameleon, in fishes, and numerous other animals. The black pigment molecules may be diffused throughout the cell or concentrated...by experiment that their concentration is caused by ex440 posure to light, by death of the animal, and by sudden section of the nerve going to tha skin... | |
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The black pigment-molecules may be diffused throughout the cell or concentrated in a mass, and all kinds of intermediate gradations may exist between diffusion and concentration. The change in colour is owing to these alterations in the molecules, the... 