. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. GROWTH AND ACTION OF EXTRACT 257 concentrations nil. (A). ml. (/?), ml. (C), ml. (£>), and ml. (E) per eye. The slope of each curve is markedly af- fected by the concentration of the solution under experiment. It is of interest to note that the concentration of an extract of one eye-stalk in ml. of fluid is well within the limits of crustacean chro- matophore activation, although it shows no apparent coleoptile elonga- tion effect. Despite the fact that the decapitated coleoptile t
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. GROWTH AND ACTION OF EXTRACT 257 concentrations nil. (A). ml. (/?), ml. (C), ml. (£>), and ml. (E) per eye. The slope of each curve is markedly af- fected by the concentration of the solution under experiment. It is of interest to note that the concentration of an extract of one eye-stalk in ml. of fluid is well within the limits of crustacean chro- matophore activation, although it shows no apparent coleoptile elonga- tion effect. Despite the fact that the decapitated coleoptile tip of Arena is less sensitive to the eye-stalk hormone of Palccmonctcs than the chro- matophores of Palcnnoiictcs, we have in the reaction of a plant to ; hormone a precise and ready method of assay which has heretofore been lacking. Under the conditions described, the results are readily repro- ducible for any given lot of Palccmonctes. There remains, of course, the desirability of devising a method of assay which will also take into account the total mass of eye-stalk material used, since presumably the o z LJ _J. I I TIME 0 UNIT= 60MIN.) FIG. 6. Effect of eye-stalk extract upon elongation of roots of amount of active extract is dependent upon the mass of glandular or other tissue of the eye-stalk producing it. Experiments to determine the effect of growth-accelerating material from the growing coleoptiles of Arena upon Palccmonetes chromato- phores have thus far been wholly negative. The concentrations used represented tip to 17 tips per milliliter of fluid extract, and no chromatophore effects were discernible with some thirty animals. Preg- nancy urine was found to be without effect on Pahcmonetcs chromato- phores. However, our tests were but preliminary and were carried out only with crudely refined material, injection of ml. of which invari- ably caused death of the crustacean. The action of eye-stalk extract upon the elongation of the root of Lupinus is
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
