. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. CHROMATOPHORIC HORMONES IN SESARMA 29 order to reject specimens in the molting phase, the early indication of the phase at the epipodite of the first maxilliped (cf. Drach, 1939) was resorted to. Isolated tissues and organs were separately ground with quartz sand to be extracted twice with distilled water. The insoluble fraction was centrifuged off, and the super- natant fluid was sealed in a glass tube and dipped into boiling water for 10 minutes. Such a preparation could be preserved for weeks and months without significan
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. CHROMATOPHORIC HORMONES IN SESARMA 29 order to reject specimens in the molting phase, the early indication of the phase at the epipodite of the first maxilliped (cf. Drach, 1939) was resorted to. Isolated tissues and organs were separately ground with quartz sand to be extracted twice with distilled water. The insoluble fraction was centrifuged off, and the super- natant fluid was sealed in a glass tube and dipped into boiling water for 10 minutes. Such a preparation could be preserved for weeks and months without significant loss of hormone activity. When needed for the assay, the samples were evaporated /';; vacua to be re-extracted with physiological saline. The final extracts were freed by filtration from coagula formed in the process of previous heating. Concentrations of extracts were expressed in terms of the number or weight of the respective tissues or organs theoretically contained in the administered doses, which were designated as (tissue equivalents). The chromatophorotropic activity of the extracts was tested chiefly upon the chromatophores of juvenile forms of Scsanna Juiemato-. o \ 60 90 TIME IN MINUTES 120 2V HOURS FIGURE 1. Curve showing time relation of pigmentary response of black chromatophores of juvenile 5. hacniatochcir following amputation of both eyestalks. chclr with carapace dimensions less than 20 mm. X 18 mm. Such individuals, in spite of the marked sluggishness in the chromatic display of adult forms of the three species of Sesarma, show a high chromatic activity, changing coloration from creamy yellow to chestnut brown uniformly over the whole dorsal aspect of the body including the walking legs. Background responses are lacking like in other color-changing crabs, and, under laboratory conditions during the day, the im- mature crabs exhibit darkening that is considerably subject to fluctuations of en- vironmental factors such as the intensity of light, moisture
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
